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  • Rat  (461)
  • Springer  (461)
  • 2020-2024
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  • 1970-1974  (123)
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  • 1
    Electronic Resource
    Electronic Resource
    Postprandial thermogenesis of rats with glutamate induced obesity in relation to energy intake (1993)
    Springer
    European journal of nutrition 32 (1993), S. 71-73 
    Details
    ISSN: 1436-6215
    Keywords: Rat ; glutamate-induced obesity ; postprandial thermogenesis ; Ratte ; Glutamat-induzierte Adipositas ; postprandiale Thermogenese
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Medicine
    Description / Table of Contents: Zusammenfassung Bei 4 Monate alten Ratten mit Glutamat-induzierter Adipositas wurde die postprandiale Thermogenese über 8 h nach Fütterung von 300, 450 und 600 kJ/kg0,75 einer Pellet-Diät mittels indirekter Kalorimetrie in computergesteuerten Stoffwechselkäfigen mit offenem Kreislauf bestimmt. Bei den adipösen Tieren war die postprandiale Thermogenese nach Aufnahme von 600 kJ/kg0,75 (oberhalb des Energieerhaltungsbedarfs) signifikant auf 40% der Thermogenese der Kontrolltiere reduziert (12,0 gegenüber 31,5 kJ/kg0,75×8 h). Es wird geschlußfolgert, daß die Ratte mit Glutamat-induzierter Adipositas als ein Tiermodell mit beeinträchtigter fakultativer Thermogenese anzusehen ist, die hauptsächlich durch eine Verminderung der sympathischen adrenergen Aktivität verursacht ist.
    Notes: Summary Postprandial thermogenesis was estimated in 4-month-old male rats with glutamate induced obesity after being fed with 300, 450 and 600 kJ/kg0.75 of a pellet diet, respectively by indirect calorimetry in computer-controlled open circuit metabolic cages over 8 h. After an intake of 600 kJ/kg0.75 (above the maintenance energy requirement) postprandial thermogenesis was significantly reduced in the obese animals to about 40% of control rats (12.0 versus 31.5 kJ/kg0.75×8 h). It is concluded that the glutamate obese rat can be accepted as an animal model with impaired facultative thermogenesis, mainly caused by a reduction of sympathetic adrenergic activity.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01610087
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  • 2
    Electronic Resource
    Electronic Resource
    Identification of brain tumours in rats using laser-induced fluorescence and haematoporphyrin derivative (1989)
    Springer
    Lasers in medical science 4 (1989), S. 241-249 
    Details
    ISSN: 1435-604X
    Keywords: Brain tumour ; Rat ; Detection ; Fluorescence ; Laser ; Haematoporphyrin derivative
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Physics , Technology
    Notes: Abstract Laser-induced fluorescence has been used for the identification of brain tumours in rats, which have been previously given tumour-seeking haematoporphyrin derivative. A pulsed nitrogen laser (λ=337 nm) was used in conjunction with an optical multichannel analyzer. For both inoculated RG-2 and TCVC rat-brain-tumour models, the blue autofluorescence was strongly reduced in the tumour compared with normal brain tissue, and at the same time the characteristic red-drug signal increased. The contrast between tumour and normal tissue was strongly enhanced by forming the ratio between the two signals. Implications for possible improvement of tumour delineation in brain tumour surgery are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02032454
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  • 3
    Electronic Resource
    Electronic Resource
    Influence of hydrochlorothiazide on the pain threshold and on the antinociceptive activity of morphine, in rats (1985)
    Springer
    Cellular and molecular life sciences 41 (1985), S. 265-266 
    Details
    ISSN: 1420-9071
    Keywords: Rat ; hydrochlorothiazide ; pain threshold ; antinociceptive activity ; analgesic activity ; morphine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Hydrochlorothiazide, acutely injected in rats, has a weak analgesic activity per se and potentiates and prolongs the antinociceptive effect of morphine.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02002628
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  • 4
    Electronic Resource
    Electronic Resource
    Effect of L-carnitine and stimulated lipolysis on muscle substrates in the exercising rat (1990)
    Springer
    Cellular and molecular life sciences 46 (1990), S. 457-458 
    Details
    ISSN: 1420-9071
    Keywords: Rat ; carnitine ; lipolysis ; exercise ; glycogen ; triglycerides ; muscle
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary To test the effect of L-carnitine on glycogen sparing when fat oxidation is increased, 100 mg/kg/d were given to rats orally for 3 days, resulting in 1.8-fold higher muscle carnitine levels. Even when FFA were raised by heparin-stimulated lipolysis, the rate of glycogen degradation was not reduced during exercise.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01954228
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  • 5
    Electronic Resource
    Electronic Resource
    Rate of normal longitudinal bone growth in the rat (1972)
    Springer
    Calcified tissue international 10 (1972), S. 238-251 
    Details
    ISSN: 1432-0827
    Keywords: Growth ; Bone ; Rat ; Tetracycline
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé La vitesse de croissance normale en longueur de la métaphyse proximale du tibia est déterminée chez le rat Sprague-Dawley entre les âges de 20 et 100 jours, en utilisant la méthode à la tétracycline. Le taux de croissance ne varie que légèrement dans les groupes d'âges différents. Il est plus élevé chez les animaux jeunes et décroit considérablement en fonction de l'augmentation de l'âge. Les rats mâles présentent une croissance plus élevée que les femelles. Cette étude a pour but de mettre au point une méthode permettant de déterminer les facteurs expérimentaux, liés à la croissance en longueur du rat.
    Abstract: Zusammenfassung Die normale Längenwachstums-Geschwindigkeit der proximalen Wachstumsplatte der Tibia wurde bei Sprague-Dawley-Ratten in einem Alter zwischen 20 und 100 Tagen mittels der Tetracyclinmethode gemessen. Die Wachstumsgeschwindigkeit variierte nur wenig innerhalb der einzelnen Altersgruppen. Die Geschwindigkeit war bei jungen Tieren am höchsten und nahm mit zunehmendem Alter beträchtlich ab. Männliche Ratten wuchsen schneller als weibliche. Diese Arbeit dient als Grundlage, um die experimentelle Beeinflussung des Längenwachstums der Ratte abschätzen zu können.
    Notes: Abstract The rate of normal growth in length from the proximal growth plate of the tibia in the Sprague-Dawley rat was measured between 20 and 100 days of age using the tetracycline method. The growth rate varied only slightly within different age groups. The rate was highest in young animals and decreased considerably with increasing age. Male rats grew faster than female. This study is intended to provide a base for an evaluation of experimental influence on the growth in length of the rat.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02012553
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  • 6
    Electronic Resource
    Electronic Resource
    Verapamil induces increased bone volume and osteopenia in female rats but has the opposite effect in male rats (1992)
    Springer
    Calcified tissue international 50 (1992), S. 524-526 
    Details
    ISSN: 1432-0827
    Keywords: Verapamil ; Bone ; Osteopenia ; Rat ; Female ; Intestinal calcium absorption
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Verapamil inhibits the intestinal absorption of calcium (Ca) and increases serum parathyroid hormone in rats. The effects of verapamil on bone tissue after long-term treatment is, however, not well described. Adult female and male Sprague-Dawley rats received verapamil in their drinking water at a dosage of 0.075 mg/ml (low dose) or 0.75 mg/ml (high dose) for 12 weeks; control rats received only drinking water. All rats were fed a diet containing 0.1% Ca and 0.5% P. In female rats, the amount of bone ash per volume was significantly reduced from 0.742 g/ml in controls to 0.713 g/ml after low-dose treatment of verapamil, and to 0.667 g/ml following high-dose treatment (P〈0.01). The tibial length was increased from 39.7 mm in controls to 40.3 mm or to 40.7 mm after low or high doses (P〈0.01). The tibial volume increased from 0.385 ml in controls to 0.397 ml after low doses and to 0.429 ml after high doses (P〈0.01). In contrast, in male rats the amount of bone ash per volume was significantly increased from 0.578 g/ml in controls to 0.580 g/ml after low doses and to 0.620 g/ml after high doses of verapamil (P〈0.01). The tibial bone volume in males as decreased from 0.633 ml in controls to 0.641 ml after low doses and to 0.583 ml after high doses (P〈0.05). The tibial length in the males was not changed by verapamil. The intestinal absorption of Ca was reduced in male rats from 5.28 in controls to 4.03 (serosa/mucosa) after low-dose treatment and to 2.46 after high-dose treatment with verapamil (P〈0.05). In female rats, the intestinal absorption of Ca did not change after verapamil treatment. Thus, chronic treatment with verapamil in female rats induced osteopenia whereas in male rats bone growth was inhibited.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00582167
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  • 7
    Electronic Resource
    Electronic Resource
    Bone blood flow and In vitro proliferation of bone marrow and trabecular bone osteoblast-like cells in ovariectomized rats (1992)
    Springer
    Calcified tissue international 50 (1992), S. 336-341 
    Details
    ISSN: 1432-0827
    Keywords: Rat ; Osteoblast-like culture ; Ovariectomy ; Estrogens ; Bone blood supply
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Ovariectomy in the rat induces a rapid osteopenia associated with an elevated bone turnover. One hundred and twenty-day-old rats were ovariectomized (OVX) or sham-operated (n=6–8 per group and per time period studied). 45Ca accretion rate and bone blood flow (microspheres trapping technique) in the femurs were determined at 28, 42, 84, and 119 days after ovariectomy. Both parameters were markedly increased by 84 days and subsided thereafter. At the 42nd day, when bone turnover was maximal, bone marrow and trabecular bone cultures were obtained from shamoperated and ovariectomized animals (n=10/group). Proliferation rate of bone marrow cells and trabecular osteoblast-like cells estimated by fibroblast colony-forming units (FCFU) efficiency and cell counting was markedly increased in primary and secondary cultures in ovariectomy. These data fitted well with the enhanced number of osteoblasts observed in situ in the long bone metaphyses of estrogen-depleted animals. As estrogens were shown in the literature to inhibit proliferation of the red cell line and of other hemopoietic lines, it is possible that estrogens, through a general mechanism, inhibit hemopoietic and stromal lines and also the proliferation of bone marrow-derived trabecular bone cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00301631
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  • 8
    Electronic Resource
    Electronic Resource
    Sustained release of salmon calcitonin in vivo from lactide: Glycolide copolymer depots (1993)
    Springer
    Calcified tissue international 52 (1993), S. 361-364 
    Details
    ISSN: 1432-0827
    Keywords: Calcitonin ; Sustained release ; Copolymer depot ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Studies were carried out to determine whether monolithic depot formulations, prepared using lactide:glycolide copolymers, could be used to administer salmon calcitonin (sCT) to rats in vivo. Formulations containing 2, 5, or 10% (w/w) sCT were administered subcutaneously to female Wistar strain rats. Release of sCT was determined by measurement of peptide in plasma using a specific radioimmunoassay and by measurement of residual sCT in the depots after recovery at postmortem. Plasma calcium concentrations and cumulative weight gain of the animals were used to measure pharmacological effects of the released sCT. Release of sCT from the depots was controlled by the copolymer and was sustained for periods up to 10 days. However, the release of sCT from the depots did not significantly alter plasma calcium concentrations, and effects on cumulative weight gain were small and transient. Peptide loading of the formulations was shown to modify sCT release. Maximal release of sCT from depots containing 10% peptide occurred over a 7 to 14-day period postadministration, with 5% sCT release occurred between days 11 and 14, and with 2% sCT, the period of maximal release was between days 11 and 18. Release of peptide from the depots was essentially complete by 21 days postadministration irrespective of the peptide loading. These data suggest that lactide:glycolide copolymer depots may have application for the convenient clinical administration of sCT in metabolic bone diseases.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00310200
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  • 9
    Electronic Resource
    Electronic Resource
    Mechanical properties, bone mineral content, and bone composition (collagen, osteocalcin, IGF-I) of the rat femur: Influence of ovariectomy and nandrolone decanoate (anabolic steroid) treatment (1993)
    Springer
    Calcified tissue international 53 (1993), S. 269-277 
    Details
    ISSN: 1432-0827
    Keywords: Bone ; Nandrolone decanoate ; Ovariectomy ; Bone mechanics ; IGF-I ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Nandrolone decanoate (ND) is an anabolic steroid with a positive effect on bone mass in osteoporotic patients. The mechanism of action, (i.e., reduction of bone resorption and/or Stimulation of bone formation), the ultimate effect on mechanical properties, and the most effective dosage are not yet clear. To address these issues, dose-related effects of the long-term effect of ND on Serum and bone biochemistry, bone mineral content, and bone mechanical properties in ovariectomized (OVX) rats (12 weeks old at the Start of the experiment) were Studied for 6 months. The results were compared with those obtained in agematched, intact, and OVX rats. OVX caused in the femur a significant increase in net periosteal bone formation and net endosteal bone resorption of bone collagen content and torsional strength, and of Serum alkaline phosphatase, osteocalcin, and insulin-like growth factor-I (IGF-I) levels, whereas cortical bone density and calcium/creatinine and phosphorus/creatinine in 24-hour urine were Significantly reduced. Treatment of OVX rats with 1 mg ND/14 days resulted in a Significant increase in periosteal bone formation, femur length, cortical and trabecular bone mineral content and density, torsion stiffness and Strength, and bone IGF-I content, and a decrease in Serum osteocalcin, urinary calcium/creatinine levels, and bone collagen content compared with OVX controls. The higher ND dosage of 2.5 mg/14 days did not improve the results. ND treatment did not reverse all changes induced by OVX to the level of the intact controls. These results indicate that ND acts as an antiresorptive drug and as a bone formation Stimulating drug. Furthermore, the increased bone mass and bone mineral density is associated with improved bone Strength and stiffness and the presence of an increased amount of IGF-I. IGF-I is a growth factor considered to play a role in the maintenance of normal skeletal balance by a paracrine or autocrine mechanism.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01320913
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  • 10
    Electronic Resource
    Electronic Resource
    The effects of the aminobisphosphonate alendronate on thyroid hormone-induced osteopenia in rats (1993)
    Springer
    Calcified tissue international 53 (1993), S. 278-282 
    Details
    ISSN: 1432-0827
    Keywords: Hyperthyroidism ; Osteopenia ; Bisphosphonate ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Hyperthyroidism, either endogenous or iatrogenic, leads to increased bone turnover and osteopenia. This study was conducted to examine (1) whether thyroid hormone excess in rats causes bone changes similar to those seen in patients with hyperthyroidism, and (2) the effects of the aminobisphosphonate alendronate on the thyroid hormone-induced bone changes. Sprague-Dawley male rats, divided into four groups, received L-thyroxine (T4) 250 μg/kg/day (+T4) or vehicle (-T4) subcutaneously six times per week and alendronate 1.75 mg/kg (+ALN) or vehicle (-ALN) orally twice a week. Rats were sacrificed after 3 weeks of treatment, blood samples were analyzed for serum T4, triiodo-L-thyronine (T3), and osteocalcin, and the proximal tibiae were processed for histomorphometric analysis. Serum T4 and T3 levels measured 20–24 hours after the last injection were 2 to 2.5-fold higher in +T4 groups than in-T4 groups. Serum osteocalcin was significantly (P 〈 0.05) higher in +T4/-ALN group than in the other groups, which were not statistically different from each other. T4 treatment (+T4/-ALN) significantly decreased the amount of cancellous bone volume (-45%) and increased osteoid surface (+254%), osteoblast surface (+111%), and osteoclast surface (+176%) relative to control values. Alendronate increased the bone volume above control values in both T4-treated (+ T4/ +ALN) and untreated (-T4/ +ALN) rats, and prevented the T4-induced increase in bone turnover in +T4/+ALN rats. It is concluded that (1) excess thyroid hormone induces cancellous bone loss associated with high bone turnover in the rat, and (2) this bone loss can be prevented by alendronate through the inhibition of osteoclastic activity.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01320914
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  • 11
    Electronic Resource
    Electronic Resource
    Immunological homologies between yeast ribosomal protein L2 and rat liver ribosomal proteins L4 and L24 (1988)
    Springer
    Current genetics 13 (1988), S. 235-239 
    Details
    ISSN: 1432-0983
    Keywords: Ribosomal protein ; Immunological homology ; Yeast ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Polyclonal antibodies raised against ribosomal protein (r-protein) L2 of Schizosaccharomyces pombe were used to check for cross-reaktions with total r-proteins of rat liver. Using this procedure, the rat liver r-proteins, L4 and L24, were identified as being immunologically related to yeast L2. In addtional, homologies between rat liver L4 and L24 were detected. The possible implications for the regulation of r-protein synthesis are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00387769
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  • 12
    Electronic Resource
    Electronic Resource
    Intra- and interspecies analyses of the carcinoembryonic antigen (CEA) gene family reveal independent evolution in primates and rodents (1989)
    Springer
    Journal of molecular evolution 29 (1989), S. 126-134 
    Details
    ISSN: 1432-1432
    Keywords: Carcinoembryonic antigen ; Evolution ; Gene family ; Human ; Rat ; Synonymous substitutions ; Silent molecular clock ; Evolutionary trees
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Various rodent and primate DNAs exhibit a stronger intra- than interspecies cross-hybridization with probes derived from the N-terminal domain exons of human and rat carcinoembryonic antigen (CEA)-like genes. Southern analyses also reveal that the human and rat CEA gene families are of similar complexity. We counted at least 10 different genes per human haploid genome. In the rat, approximately seven to nine different N-terminal domain exons that presumably represent different genes appear to be present. We were able to assign the corresponding genomic restriction endonuclease fragments to already isolated CEA gene family members of both human and rat. Highly similar subgroups, as found within the human CEA gene family, seem to be absent from the rat genome. Hybridization with an intron probe from the human nonspecific cross-reacting antigen (NCA) gene and analysis of DNA sequence data indicate the conservation of noncoding regions among CEA-like genes within primates, implicating that whole gene units may have been duplicated. With the help of a computer program and by calculating the rate of synonymous substitutions, evolutionary trees have been derived. From this, we propose that an independent parallel evolution, leading to different CEA gene families, must have taken place in, at least, the primate and rodent orders.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02100111
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  • 13
    Electronic Resource
    Electronic Resource
    An analysis of codon usage in mammals: Selection or mutation bias? (1991)
    Springer
    Journal of molecular evolution 33 (1991), S. 442-449 
    Details
    ISSN: 1432-1432
    Keywords: Humans ; Mouse ; Rat ; Codon usage ; Mutation bias ; Selection
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary A new statistical test has been developed to detect selection on silent sites. This test compares the codon usage within a gene and thus does not require knowledge of which genes are under the greatest selection, that there exist common trends in codon usage across genes, or that genes have the same mutation pattern. It also controls for mutational biases that might be introduced by the adjacent bases. The test was applied to 62 mammalian sequences, the significant codon usage biases were detected in all three species examined (humans, rats, and mice). However, these biases appear not to be the consequence of selection, but of the first base pair in the codon influencing the mutation pattern at the third position.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02103136
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  • 14
    Electronic Resource
    Electronic Resource
    The influence of tactile stimulation of nipples on the milk ejection reflex in the rat (1992)
    Springer
    Journal of comparative physiology 170 (1992), S. 645-650 
    Details
    ISSN: 1432-1351
    Keywords: Milk ejection reflex ; Positive pressure oscillations ; Motor activity of pups ; Tactile stimulation of nipples ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Changes of positive pressure exerted by pups on nipples during sucking were investigated using anesthetized, lactating dams. It was found that, every 50–60 s, individual pups performed bouts of pressure oscillations (3/s) of high amplitude which lasted about 10–12 s and coincided with periods of increased motor activity. During the intervals, when pups were quiet, series of low-amplitude oscillations (3/s) were also observed. Using a strain measuring method to record the activity of sucking pups, synchronization of activity of two or more pups was found to occur periodically every 25–30 s and, most frequently, 10–30 s before the reflex increase of milk pressure. In further experiments, artificial tactile stimulation was applied to the dam's nipples using the joint action of suction and positive pressure. Following a short-term (10–20 s) increase in frequency and amplitude of artificial nipple stimulation, 60%–80% of all reflexive peaks of milk pressure were elicited with a latency of 19 ± 5 s. This suggests that there are specific conditions under which the stimulation of nipples by pups may trigger the formation of the milk ejection reflex in the rat.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00199340
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  • 15
    Electronic Resource
    Electronic Resource
    Effects of lesion of the inferior olivary complex by 3-acetylpyridine on learning and memory in the rat (1992)
    Springer
    Journal of comparative physiology 171 (1992), S. 657-664 
    Details
    ISSN: 1432-1351
    Keywords: Inferior olivary complex ; Cerebellum ; 3-acetylpyridine ; Harmaline ; Learning ; Memory ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary DA/HAN-strained male rats (pigmented rats) were submitted to two experimental tasks consisting of spatial learning (water-escape) and a passive avoidance conditioning. Both these tasks were performed by different animals. In order to destroy the inferior olivary complex, the animals were injected with 3-acetylpyridine either 9 days prior to the initial learning session or 24 h after completion of the learning task. They were retested (retrieval test) 10 days after the initial learning was achieved. Learning and retention were compared to those noted in control rats. Administration of 3-acetylpyridine before the initial learning did not prevent the spatial learning but the scores were greatly altered and the number of trials needed to reach the fixed learning criterion was much greater than in controls. However, 10 days later the animals had memorized their initial experience. Injection of 3-acetylpyridine after the initial learning session impaired memory: the animals had completely forgotten their initial learning. It can therefore be concluded that lesion of the afferent climbing fibres to the cerebellar cortex alters learning and retention of a spatial task. Such a lesion does not interfere with learning and retention of a passive avoidance conditioning, since in this condition the experimental animals injected with 3-acetylpyridine either before or after the initial learning behave similarly to controls. The effects of the inferior olivary complex lesion are obviously different according to the task to be learnt, suggesting that these two tasks do not require the integrity of the same nervous structures.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00194113
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  • 16
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    Electronic Resource
    Qualitative and quantitative variability in different classes of proteins: Comparison of mouse and rat (1987)
    Springer
    Journal of molecular evolution 24 (1987), S. 260-271 
    Details
    ISSN: 1432-1432
    Keywords: Mouse ; Rat ; Two-dimensional electrophoresis ; Quantitative variability of proteins ; Qualitative variability of proteins ; Protein classes ; Membrane proteins ; Organ-specific proteins ; Regulatory genes ; Speciation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Proteins of membranes and cytosols were extracted from the livers and brains of mice (inbred strain DBA/6J) and rats (inbred strain DA/Han) and separated by two-dimensional electrophoresis (2-DE). The 2-DE patterns were compared with regard to qualitative (spot position) and quantitative (spot intensity) characteristics of the proteins of these two species. The following results were obtained: (1) Brain had more (higher percentage) conservative proteins (proteins found in both mice and rats) than liver; (2) plasma membranes had more conservative proteins than the cytosols; (3) organ-unspecific proteins contained more conservative proteins than relatively organ-specific proteins; (4) the pattern of distribution of genetic variability among different classes of proteins represented by findings 1–3 was the same for the qualitative and quantative characteristics of the proteins; and (5) some observations indicated that quantitative variability occurred more frequently among proteins than did qualitative variability. Our conclusion is that regulatory sequences in the DNA (regulatory genes) are subjected to functional constraints that differ in strength among different classes of proteins by the same ratios as the constraints acting on the structural genes. The overall effect of the selective pressure is, however, less stringent for regulatory genes than for structural genes. The results obtained here by comparing two different species are very similar to previous results we obtained by studying different subspecies (inbred strains of the mouse). From this finding arises a new concept: the study of molecular evolution on the basis of different classes of proteins. Our results were compared with data from the literature that were obtained in part from studies on cultured cells. The comparison suggested that cultured cells have lost their tissue-specific proteins, and so generate predominantly extremely conservative proteins.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02111239
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  • 17
    Electronic Resource
    Electronic Resource
    Distribution of vitamin A in various organs of rats in relation to the quality and the quantity of dietary proteins (1987)
    Springer
    European journal of nutrition 26 (1987), S. 43-51 
    Details
    ISSN: 1436-6215
    Keywords: Dietary protein ; Vitamin A ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Medicine
    Description / Table of Contents: Zusammenfassung Es wurde der Einfluß von Qualität und Quantität von Nahrungsproteinen auf die Verteilung einer einzigen massiven Dosis von Vitamin A in verschiedenen Organen wachsender Wistar-Ratten untersucht. Die Untersuchungen wurden mit Casein- und Bengal-Gram-Diäten mit 20 % und 10 % Proteingehalt und auch mit radioaktiv markiertem Retinylacetat durchgeführt. Die Ergebnisse zeigen, daß die Leberspeicherung sowohl von Vitamin A aus der Nahrung als auch die einer einzigen starken Vitamin-A-Gabe (20 000 I.U.) stark herabgesetzt war bei Ratten, die nach der Bengal-Gram-Diät gefüttert wurden, verglichen mit Ratten, die auf Casein-Diät gesetzt waren. Im Gegensatz zur Leberspeicherung ist das Vitamin-A-Niveau im Plasma in allen Gruppen vergleichbar. Füttern niedriger Protein-Qualität reduzierte die Gewebeverteilung von [3H]-Retinylacetat sowohl bei Kontrollratten als auch bei solchen, denen eine massive Dosis Vitamin A gegeben wurde. Diese Untersuchung läßt vermuten, daß sowohl schlechte Qualität als auch unzureichende Mengen von Nahrungsproteinen nachteilige Einflüsse auf den Vitamin-A-Zustand wachsender Ratten haben.
    Notes: Summary The influence of the quality and the quantity of dietary proteins on the distribution of a single massive dose of vitamin A in various organs of growing Wistar strain rats has been studied by using casein and bengal gram diets at 20 % and 10 % protein levels. The distribution of [3H]-retinyl acetate in various tissues was also investigated in these dietary conditions. The results show that the hepatic storage of dietary as well as a single massive dose (20,000 I.U.) of vitamin A was profoundly decreased in the rats fed on bengal gram diets as compared to those fed on casein diets. Regardless of hepatic stores, the plasma vitamin A levels were comparable in all the groups. Feeding of low quality of protein reduced the tissue distribution of [3H]-retinyl acetate in control as well as rats given a massive dose of vitamin A. This study suggests that both the poor quality and the inadequate quantity of dietary protein are detrimental influences on the vitamin A status of the growing rats.
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    URL: http://dx.doi.org/10.1007/BF02023818
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    An experimental model of ascending pyelonephritis due toCandida albicans in rats (1993)
    Springer
    Mycopathologia 123 (1993), S. 149-154 
    Details
    ISSN: 1573-0832
    Keywords: Ascending pyelonephritis ; Candida albicans ; Experimental model ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract We developed a new experimental model of ascendingCandida pyelonephritis in female rats with leukopenia and vesicoureteral reflux. Rats were treated transperitoneally with cyclophosphamide (200 mg/kg) to induce leukopenia 3 days before and transurethrally with diluted acetic acid solution to induce vesicoureteral reflux 1 day before inoculation ofCandida albicans strain, ATCC 10259 (containing 107 cells). Microscopy revealed acute pyelonephritis in whichCandida cells invaded from the fornix and/or papilla into the medulla within 3 days after inoculation. Between 7 and 28 days after inoculation, chronic pyelonephritis reached the cortex. The incidence of pyelonephritis increased gradually and was approximately 80% after 7 days.Candida colony counts of bladder urine specimens obtained by direct puncture were significantly greater in rats with pyelonephritis extending into the parenchyma than in those with pyelonephritis located along the pelvis (p〈0.01). These results suggest that this rat model shows the characteristic feature of ascending pyelonephritis due toC. albicans and that the severity ofCandida pyelonephritis can be estimated fromCandida counts of bladder urine.
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    URL: http://dx.doi.org/10.1007/BF01111265
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    Renal eicosanoids and blood pressure in genetically hypertensive rats of the lyon strain (1994)
    Springer
    Journal of biomedical science 1 (1994), S. 201-203 
    Details
    ISSN: 1423-0127
    Keywords: Hypertension ; Eicosanoid ; Rat ; Genetics ; Kidney
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The present paper reviews the evidence for a possible involvement of renal eicosanoids in the pathophysiology of high blood pressure in genetically hypertensive rats of the Lyon strain. Both in vivo and in vitro experiments suggest that an increased ability to synthesize the vasoconstrictor prostaglandin H2 and/or thromboxane A2 in renal vessels (1) acts as an autocrine amplifier of pressor agents and (2) may contribute to resetting the pressure natriuresis curve which is a prerequisite for the development and maintenance of hypertension.
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    URL: http://dx.doi.org/10.1007/BF02253302
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    Tall gut formation in the rat embryo (1985)
    Springer
    Development genes and evolution 194 (1985), S. 429-432 
    Details
    ISSN: 1432-041X
    Keywords: Tail bud ; Tail gut ; Gut ; Organogenesis ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The formation of the tail portion of the primitive gut was investigated by light and electron microscopy in 10- and 11-day rat embryos. The observations permit the conclusion that the tail gut does not form as a posterior extension of the hindgut but originates from the tail bud mesenchyme by mechanism analogous to the secondary neurulation. It includes cell condensation, aquisition of apicobasal polarity and the radial, rosette-like arrangement around a central cavity. These cells bear the cytological characteristics of both the absorptive epithelial cells and the mesenchymal cells at their apical (adluminal) and abluminal ends respectively.
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    URL: http://dx.doi.org/10.1007/BF00848557
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    Changes in brush-border enzyme activities of intestinal epithelial cells isolated from the villus-crypt axis during the early phase of alloxan diabetes in rats (1985)
    Springer
    Cellular and molecular life sciences 41 (1985), S. 482-484 
    Details
    ISSN: 1420-9071
    Keywords: Rat ; alloxan diabetes ; intestinal villus ; alkaline phosphatase ; sucrase ; epithelial cells ; villus-crypt axis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The sucrase activity in enterocytes isolated from the villus crypt axis was found to increase in all regions of the villus from day 2 after induction of diabetes, and the increase continued until day 4. In contrast, alkaline phosphatase activity increased mainly in the apical one-third of the villus-crypt column, and the increase occurred abruptly on day 4 with increase in food intake.
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    URL: http://dx.doi.org/10.1007/BF01966159
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    Basal plasma corticosterone level after bilateral selective lesions of thee olfactory pathways in the rat (1986)
    Springer
    Cellular and molecular life sciences 42 (1986), S. 169-171 
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    ISSN: 1420-9071
    Keywords: Rat ; olfactory pathway selective lesions ; plasma corticosterone ; lactacidemia ; adrenal glands
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In comparison to control rats, basal plasma corticosterone level and lactacidemia significantly increased in rats submitted to a bilateral lesion of the lateral olfactory tract and/or the anterior branch of the anterior commissure. Only the anterior branch of the anterior commissure induced hyperglycemia; that of the lateral olfactory tract exerted an opposite effect.
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    URL: http://dx.doi.org/10.1007/BF01952451
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    Cell allocation to the inner cell mass and the trophectoderm in rat embryos during in vivo preimplantation development (1990)
    Springer
    Development genes and evolution 198 (1990), S. 257-263 
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    ISSN: 1432-041X
    Keywords: Inner cell mass ; Blastocyst ; Morula ; Implantation ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The number of trophectoderm (TE) and inner cell mass (ICM) cells was determined by complementmediated lysis and differential staining in rat embryos collected at different times during in vivo preimplantation development. At 90 h after fertilization, two groups of morulae were discriminated according to the presence or absence of detectable ICM cells, and the analysis of their total cell number indicated that acquisition of a permeability seal between TE cells begins at the 14-cell stage. On the other hand, our data confirmed that blastocoele formation occurs after the fourth cleavage division in the rat. The total cell number increased exponentially with time in blastocysts recovered between 90 h and 127 h but the cell kinetics of TE and ICM cells were different. The proportion of ICM cells consequently varied throughout blastocyst development, with a peak value for expanded blastocysts at 103 h. Finally, a linear-quadratic relationship was found between the numbers of TE and ICM cells when all the embryos with a detectable ICM were analysed together.
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    URL: http://dx.doi.org/10.1007/BF00377392
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    Effects of β-hydroxybutyrate on rat embryos grown in culture (1985)
    Springer
    Cellular and molecular life sciences 41 (1985), S. 273-275 
    Details
    ISSN: 1420-9071
    Keywords: Rat ; embryo ; embryo ; rat ; β-hydroxybutyrate ; diabetes ; maternal ; fetal malformation ; malformation ; fetal ; ketone bodies
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In order to investigate further the relationship between maternal diabetes and fetal malformation, rat embryos were grown in vitro in the presence of β-hydroxybutyrate, one of the ketone bodies produced by diabetics. At 10 mM, β-hydroxybutyrate produced minor abnormalities and at 20 mM it produced major abnormalities in rat embryos.
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    URL: http://dx.doi.org/10.1007/BF02002633
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    The effects of sodium fluoride on bone breaking strength (1974)
    Springer
    Calcified tissue international 14 (1974), S. 283-289 
    Details
    ISSN: 1432-0827
    Keywords: Sodium fluoride ; Osteoporosis ; Bone ; Strength ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé L'utilisation thérapeutique de fluorure de sodium a été recommandée dans le traitement de diverses maladies osseuses ostéopéniques. Cet emploi est basé principalement sur les effects ostéosclérotiques bien connus du fluorure de sodium, mais on connait mal son effet sur la force de résistance osseuse. L'influence de diverses concentrations de fluorure de sodium sur la force de résistance osseuse de jeunes rats soumis à des régimes riches et pauvres en calcium a été étudiée. L'administration de fluorure de sodium augmente le diamètre osseux, indiquant une stimulation de la formation de l'os périosté, mais la force de résistance osseuse est réduite ou non modifiée par l'ingestion de fluor.
    Abstract: Zusammenfassung Die therapeutische Verwendung von Natriumfluorid ist für eine Anzahl von Knochenmangel-Krankheiten empfohlen worden. Die Empfehlungen basieren hauptsächlich auf den bekannten osteosklerotischen Wirkungen von Natriumfluorid; über dessen Effekt auf die Knochenstärke ist wenig bekannt. In dieser Arbeit wurde der Einfluß verschiedener Konzentrationen von Natriumfluorid auf die Knochenstärken von wachsenden Ratten mit hoher und niederer Calciumeinnahme untersucht. Die Verabreichung von Natriumfluorid erhöhte den Knochendurchmesser, was auf eine Stimulierung der Periostbildung hinwies, die Knochenstärke wurde jedoch durch Fluorideinnahme herabgesetzt oder nicht beeinflußt.
    Notes: Abstract The therapeutic use of sodium fluoride has been recommended in a variety of osteopenic bone diseases. The recommendations are based mainly on the known osteosclerotic effects of sodium fluoride and little information is available as to its effect on bone strength. The influence of various concentrations of sodium fluoride on bone strength in growing rats on high and low calcium diets was studied. The administration of sodium fluoride increased bone diameter, indicating stimulation of periosteal bone formation, but bone strength was reduced or not affected by fluoride ingestion.
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    Cell kinetics and morphology of the growth plate in the normal and hypophysectomized rat (1973)
    Springer
    Calcified tissue international 13 (1973), S. 113-129 
    Details
    ISSN: 1432-0827
    Keywords: Kinetics ; Growth ; Epiphyses ; Hypophysectomy ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé La largeur de la métaphyse tibiale, la zone indifférenciée, la zone sériée et les cellules en dégénerescence ont été observées chez des rats Sprague-Dawley normaux et hypophysectomisés. La production cellulaire de la métaphyse est déterminée sur la base de la croissance osseuse longitudinale déterminée par l'oxytétracycline et la taille des cellules en dégénérescence. La diminution de la croissance osseuse longitudinale, en fonction de l'augmentation de l'âge et après hypophysectomie, est due partiellement, à la diminution de production cellulaire et partiellement à une décroissance de la taille des cellules en dégénérescence dans la métaphyse. L'influence de la production cellulaire et de l'activité mitotique prédomine.
    Abstract: Zusammenfassung Die Breite der proximalen Wachstumsplatte der Tibia, deren undifferenzierter und säulenförmiger Zone und die Größe der nahe bei der Metaphyse auftretenden degenerativen Zellen wurden in normalen und hypophysektomierten Sprague-Dawley-Ratten bestimmt. Die Zellproduktion in der Wachstumsplatte wurde aus dem longitudinalen Knochenwachstum berechnet, welches mittels Oxytetracyclin und der Größe der degenerativen Zellen bestimmt wurde. Es wurde festgestellt, daß die Abnahme des longitudinalen Knochenwachstums bei zunehmendem Alter und nach Hypophysektomie zum Teil einem Rückgang in der Zellproduktion, zum Teil einer Verminderung der Größe der degenerativen Zellen in der Wachstumsplatte zuzuschreiben ist. Der Einfluß der Zellproduktion, und somit der mitotischen Aktivität, herrscht vor.
    Notes: Abstract The width of the proximal growth plate of the tibia, its undifferentiated and columnar zone and the size of the degenerative cell close to the metaphysis, were determined in normal and hypophysectomized Sprague-Dawley rats. The cell production in the growth plate was calculated from the longitudinal bone growth determined with oxytetracycline and the degenerative cell size. It was found that the decrease in longitudinal bone growth with increasing age and after hypophysectomy, is due partly to a decrease in cell production, and partly to a decrease in degenerative cell size in the growth plate. The influence of cell production and thus the mitotic activity predominates.
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    URL: http://dx.doi.org/10.1007/BF02015402
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    Effect of a five-week swimming program on rat bone: A histomorphometric study (1992)
    Springer
    Calcified tissue international 51 (1992), S. 137-142 
    Details
    ISSN: 1432-0827
    Keywords: Swimming exercise ; Bone histomorphometry ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary To specify the exercise-induced changes on different skeletal sites, the effect of a 5-week endurance swin training was studied in rats. Eighteen Lyon strain (Sprague-Dawley) 5-week old female rats were divided into nine sedentary and nine swimming rats. Each swim training session was increased by 15 minutes from 2–6 hours per day. A histomorphometric study was performed at the primary and secondary spongiosa of the distal femur and at the secondary spongiosa of lumbar and thoracic vertebral bodies. After training, bone loss was observed in the secondary spongiosa of lumbar vertebral bodies (24.7%) and in the primary spongiosa of distal femur (15.2%). A tendency to bone loss was also detected in the secondary spongiosa of distal femur (10.8%), whereas no change was detected in thoracic vertebral bodies. In secondary spongiosa, bone loss was accompanied with a thinning of trabeculae. Total eroded surfaces and osteoid surfaces were significantly decreased in the three studied skeletal sites, suggesting a decreased bone turnover. The decreased thickness of osteoid seams in both lumbar vertebrae and distal femur could mean that the osteoblastic activity has also been altered at the cell level, leading to thinning of trabeculae. Five-week swim training with such duration and intensity of exercise appears unable to increase bone volume in rats and, therefore, causes adverse effects. The three studied bones seemed to adapt differently to experimental conditions. The lack of ground reaction forces induced by water immersion might have contributed to the observed bone loss. “Normal” gravity would be an important cofactor in the osteogenic effects of exercise.
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    URL: http://dx.doi.org/10.1007/BF00298502
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    Biphasic dose-response curves of cortisol effects on rat diaphyseal bone biomechanics (1992)
    Springer
    Calcified tissue international 50 (1992), S. 49-54 
    Details
    ISSN: 1432-0827
    Keywords: Cortisol ; Cortical bone ; Bone biomechanics ; Rat ; Femur
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Doses of 8, 16 (low), 32, 48, 64 (medium), and 150 (high) mg/kg/day of cortisol were administered to groups of 8 growing rats each during 16 days, and their femurs were then submitted to 3-point bending tests at low strain rate. Low doses had no effect. Medium doses, previously shown to improve calcium (Ca) balance and weight gain in the species, augmented diaphyseal elastic and ultimate strength, stiffness, and plastic-to-elastic deformation ratio with respect to untreated controls. This effect was achieved either by enhancing bone mass (volume, sectional moment of inertia, wall/lumen ratio) without changes in material quality parameters (32 mg/kg/day) or, conversely, by increasing bone tissue mechanical properties (stress, modulus of elasticity) not affecting bone geometry (48 and 64 mg/kg/day). The highest dose, known to depress Ca balance and weight gain, impaired diaphyseal mechanical performance in controls by substantially reducing bone mass without major variation in bone material properties, that is, developing a true osteopenic state in mechanical terms. The energy elastically absorbed per unit volume (proportional to the risk of comminute fractures) was greater with the highest dose because of enhanced deformability and diminished bone mass. The biphasic dose-response curves obtained, grossly parallel to those previously demonstrated for metabolic actions of cortisol in the same species, showed that biomechanical repercussion of this treatment on bone depends on different, dose-dependent effects which vary independently in temporal course, intensity, and sign.
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    URL: http://dx.doi.org/10.1007/BF00297297
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    Noninvasive loading of the rat ulna in vivo induces a strain-related modeling response uncomplicated by trauma or periostal pressure (1994)
    Springer
    Calcified tissue international 54 (1994), S. 241-247 
    Details
    ISSN: 1432-0827
    Keywords: Loading ; Strain ; Modeling ; Rat ; Ulna
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Abstract Adaptive changes in bone modeling in response to noninvasive, cyclic axial loading of the rat ulna were compared with those using 4-point bending of the tibia. Twenty cycles daily of 4-point bending for 10 days were applied to rat tibiae through loading points 23 and 11 mm apart. Control bones received nonbending loads through loading points 11 mm apart. As woven bone was produced in both situations, any strain-related response was confounded by the response to direct periosteal pressure. Four-point bending is not, therefore, an ideal mode of loading for the investigation of strain-related adaptive modeling. The ulna's adaptive response to daily axial loading over 9 days was investigated in 30 rats. Groups 1–3 were loaded for 1200 cycles: Group 1 at 10 Hz and 20 N, Group 2 at 10 Hz and 15 N, and Group 3 at 20 Hz and 15 N. Groups 4 and 5 received 12,000 cycles of 20 N and 15 N at 10 Hz. Groups 1 and 4 showed a similar amount of new bone formation. Group 4 showed the same pattern of response but in reduced amount. The responses in Groups 2 and 3 were either small or absent. Strains were measured with single-element, miniature strain gauges bonded around the circumference of dissected bones. The 20 N loading induced peak strains of 3500–4500 μstrain. The width of the periosteal new bone response was proportional to the longitudinal strain at each point around the bone's circumference. It appears that when a bone is loaded in a normal strain distribution, an osteogenic response occurs when peak physiological strains are exceeded. In this situation the amount of new bone formed at each location is proportional to the local surface strain. Cycle numbers between 1200 and 12,000, and cycle frequencies between 10 and 20 Hz have no effect on the bone's adaptive response.
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    URL: http://dx.doi.org/10.1007/BF00301686
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    Effect of running exercise on the bone loss induced by orchidectomy in the rat (1994)
    Springer
    Calcified tissue international 55 (1994), S. 33-37 
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    ISSN: 1432-0827
    Keywords: Osteoporosis ; Rat ; Orchidectomy ; Exercise ; Strength
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Abstract The effect of exercise on castration-induced osteoporosis in 3-month-old male rats weighing 264±4 g at the beginning of the experiment was studied. A testosterone deficiency was induced by orchidectomy (ORC), and the exercise group ran 10 m/minute for 1 hour a day on a treadmill at 0% grade. There were seven groups of eight rats (n=56) randomized into a control group killed at time 0, and sham, ORC and ORC and exercise groups killed at 4 and 8 weeks. ORC reduced body weight gain (with analysis of variance (ANOVA) P〈0.001), and at 4 weeks the body weight was 343±14 g in ORC group and 301±4 g in the ORC and exercise group (P〈0.01). The increase in femoral length was slower in the ORC+exercise groups. The ash weight of the tibia did not decrease significantly after ORC or ORC+ exercise. ORC did not affect 45Ca incorporation, but exercise slightly increased it in the whole tibia 8 weeks after ORC (with ANOVA P=0.057). ORC had significantly lowered the trabecular bone volume in the secondary spongiosa of the distal femur at 4 and 8 weeks, and exercise did not prevent this. This is an opposite finding to our previous study with ovariectomized female rats [12]. ORC also significantly had reduced the osteoblast-lined trabecular bone surface and the number of osteoclasts by 8 weeks after the operation. Exercise increased the osteoblast-lined surface and the number of osteoclasts. The mechanical strength of the femoral neck also was reduced after ORC and this was not prevented by exercise either. In conclusion, ORC reduces bone growth and turnover which leads to osteopenia in growing rats. Moderate treadmill exercise does not reverse the ORC-induced loss of trabecular bone and the reduced mechanical strength of the femoral neck, although it has a positive effect on the osteoblast and osteoclast indices and on calcium incorporation into bone.
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    URL: http://dx.doi.org/10.1007/BF00310166
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    Different forms of alkaline phosphatase in adult rat femur. Effect of a Vitamin D3-deficient diet and of a sorbitol-enriched diet (1992)
    Springer
    Calcified tissue international 50 (1992), S. 433-438 
    Details
    ISSN: 1432-0827
    Keywords: Bone alkaline phosphatase ; Rat ; Vitamin D ; Sorbitol
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary In the femoral extremities of the adult rat containing the metaphysis, the epiphyseal cartilage, and the epiphysis, four alkaline phosphatase (AP) forms were distinguished on polyacrylamide gel electrophoresis. Two soluble forms were present in the 160,000 g supernatant: one of Mr 165 kDa and another of Mr 110–115 kDa, which exhibited a strong catalytical activity. Moreover, from the pellet, three membrane-bound forms of Mr 130, 110–115, and 100 kDa could be extacted with sodium deoxycholate. When denaturated AP was visualized by postelectrophoretic autoradiography of the phosphorylated intermediates, subunits always appeared as three monomers of Mr 75–80, 60–70, and 50–60 kDa. As four native forms but only three types of subunits were found to be present in the femur, it seems that, apart from homodimers, some heterodimers could also occur. Three types of diets were administered to three groups of rats for 5 weeks. Two are known to disturb bone mineralization: (1) a vitamin D3-deficient diet, and (2) the same as (1) but enriched with 12% sorbitol. The third was a normal diet containing vitamin D3. Concerning the effects on AP of dietary sorbitol and the vitamin D3-deficient diet, it was found that rats receiving the diet supplemented with sorbitol showed a substantial rise in the activity of the Mr 165 kDa form with the concomitant appearance of a new monomer of Mr 100 kDa. In contrast, rats fed the vitamin D3-deficient diet always displayed an increase in enzyme activity, principally of the Mr 100 and 110 kDa forms. In conclusion, the femur extracts of normal rats contained different forms of AP: either soluble 110–115 and 165 kDa forms or membrane-bound 130, 110–115, and 100 kDa forms. The administration of sorbitol-enriched diet induced a marked increase of the 165 kDa form whereas the administration of vitamin D3-deficient diet increased the 100 and 110 kDa forms.
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    URL: http://dx.doi.org/10.1007/BF00296774
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    Synthetic parathyroid hormone-like protein (1–74) is anabolic for bone in vivo (1992)
    Springer
    Calcified tissue international 51 (1992), S. 30-34 
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    ISSN: 1432-0827
    Keywords: PTHRP ; Anabolic ; Rat ; Bone ; Potency
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Parathyroid hormone-related protein (PTHRP) has recently been purified from human tumors associated with the syndrome of humoral hypercalcemia of malignancy. The gene encoding PTHRP has been cloned, and based on predicted amino acid sequence, polypeptides comprising the first 36 [36Tyr(1–36) PTHRP amide] and 74 [(1–74)PTHRP] amino acids have been synthesized. Human (h) PTHRP (1–36) and (1–74) are potent bone-resorbing agents, and are catabolic for bone in vivo when given continuously at high doses. Bovine parathyroid hormone (bPTH) (1–34) is also catabolic for bone at high dose levels, but when given in low doses for weeks to months, it is anabolic. Although PTHRP possess several PTH-like properties in bone, hPTHRP (1–34) is reported to be only weakly anabolic in vivo. As polypeptide length influences PTHRP action, we evaluated hPTHRP(1–74) as an anabolic agent for bone in vivo. Twenty-four 4-week-old male Sprague-Dawley rats were given daily subcutaneous injections of hPTHRP(1–74) (1 and 2 nmol/100 g body weight, bw), bPTH(1–34) (4 nmol/100 g bw) or vehicle. Rats were sacrificed on day 12, and serum calcium, phosphorus, and 1,25 dihydroxyvitamin D and femoral bone dry weight, calcium content, and hydroxyproline content were measured. Serum calcium and phosphorus were equivalent in all groups. A significant increase in dry bone weight was observed in both PTHRP-treated groups compared with controls. PTHRP also caused a significant, dose-dependent increase in bone calcium and hydroxypro-line content. Results of these studies indicate that PTHRP (1–74) is anabolic for bone in vivo when administered at low-dosage levels for a prolonged period.
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    URL: http://dx.doi.org/10.1007/BF00296214
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    The in vivo effect of a new, in vitro, extremely potent vitamin D3 analog KH1060 on the suppression of renal allograft rejection in the rat (1994)
    Springer
    Calcified tissue international 54 (1994), S. 150-154 
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    ISSN: 1432-0827
    Keywords: Vitamin D analog ; KH1060 ; Kidney transplantation ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Abstract KH1060 is a new 20-epi-vitamin D3 analog, which has exerted a considerable immunosuppressive potency in vitro. We have tested in vivo the effect of KH1060 on the suppression of renal allograft rejection in the rat. Allogenic kidney transplantation from DA donor rats to Lewis recipient rats treated intraperitoneally with KH1060 in doses from 0.2 to 6 μg/kg/day, or saline (placebo group), or CyA 10 mg/kg/day for 10 days (positive control group), was performed. Median graft survival time in KH1060-treated groups was 7–9 days, in the placebo group 6 days, whereas CyA led to long-term graft survival, 34 days in 50% of rats and 〉100 days in 50% of rats. In vivo, KH1060 failed to prolong renal allograft survival considerably, and led to development of hypercalcemia. Our results stress the existence of a large discrepancy between the in vitro and in vivo immunoregulatory effects of this vitamin D analog.
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    Effect of 1α-vitamin D3 on bone strength and composition in growing rats with and without corticosteroid treatment (1994)
    Springer
    Calcified tissue international 55 (1994), S. 443-450 
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    ISSN: 1432-0827
    Keywords: Bone mechanics ; Bone composition ; Vitamin D3 ; Corticosteroid ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Abstract The effects of 1α-vitamin D3 were studied for 6 months in 2-month-old male and female rats on a moderately low calcium diet with or without low-dose prednisolone treatment. Both cortical bone mechanical and biochemical properties were examined. Femoral bone specimens were subjected to torsional loading tests. With age, bone strength and stiffness increased in both sexes, accompanied by an increased degree of mineralization (bone ash and calcium concentrations). During growth, strength and stiffness increased more in male than in female rats. When 1α-vitamin D3 (0.5 μg/kg/day) was given alone, bone mechanical competence improved significantly whereas insulin-like growth factor-I (IGF-I) and calcium concentrations in the bone matrix were significantly reduced. Treatment with low-dose prednisolone (0.5 mg/kg/day) alone did not influence bone mechanical properties compared with intact control rats (without prednisolone) although a significant reduction in calcium concentration and an increased phosphorus concentration were measured. A combined therapy with prednisolone and 1α-vitamin D3 significantly increased bone strength, toughness, and stiffness compared with control bones. Both mineralization degree (ash and calcium concentration) and IGF-I concentration were decreased. We conclude that (1) mechanical properties of rat cortical bones improve relatively more in males compared with agematched females during growth which is related to increased bone mass and size, (2) low-dose prednisolone treatment does not change mechanical properties in males, and altered them only nonsignificantly in females despite a change in mineralization degree in both sexes; (3) treatment with 1α-vitamin D3 results in a consistent increase in mechanical competence of the bone accompanied by a significant decrease in IGF-I concentration in the bone matrix.
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    Epilepsy and electromagnetic fields: effects of simulated atmospherics and 100-Hz magnetic fields on audiogenic seizure in rats (1988)
    Springer
    International journal of biometeorology 32 (1988), S. 17-20 
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    ISSN: 1432-1254
    Keywords: Epilepsy ; Electromagnetic fields ; Rat ; Audiogenic seizure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geography , Physics
    Notes: Abstract In order to study the possible association between epileptic seizures and natural electromagnetic fields, 32 female audiogenic seizure (AGS)-susceptible rats were exposed to simulated 10 kHz and 28 kHz atmospherics and to a sinusoidally oscillating magnetic field with a frequency of 100 Hz and field strength of 1 A/m. After the electromagnetic exposure, seizures were induced in the rats with a sound stimulus. The severity of the seizure was determined on an ordinal scale, the audiogenic response score (ARS). The time from the beginning of the sound stimulus to the onset of the seizure (seizure latency) and the duration of the convulsion was measured. No differences from the control experiments were found in the experiments with simulated atmospherics, but the 100 Hz magnetic field increased the seizure latency by about 13% (P〈0.02). The results do not support the hypothesis that natural atmospheric electromagnetic signals could affect the onset of epileptic seizures, but they suggest that AGS-susceptible rats may be a useful model for studying the biological effects of electromagnetic fields.
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    URL: http://dx.doi.org/10.1007/BF01623987
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    Peripheral nervous control of cold-induced reduction in the respiratory quotient of the rat (1990)
    Springer
    International journal of biometeorology 34 (1990), S. 24-27 
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    ISSN: 1432-1254
    Keywords: Cold-induced thermogenesis ; Peripheral nervous system ; Respiratory quotient ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geography , Physics
    Notes: Abstract Cold-exposed rats show a reduction in the respiratory quotient which is indicative of a relative shift from carbohydrates to lipids as substrates for oxidative metabolism. In the present study, the effects of food deprivation and cold exposure on the respiratory quotient were observed. In addition, the involvement of the three main branches of the peripheral nervous system (sympathetic, parasympathetic, and somatic) was investigated by means of synaptic blockade with propranolol, atropine, and quinine, respectively. Both propranolol and quinine blocked the cold-induced decrease in respiratory quotient and increase in heat production, whereas atropine had only minor and very brief effects. It is concluded that both the sympathetic and somatic branches are involved in the metabolic changes associated with cold-induced thermogenesis and that the increase in metabolic heat production involves a shift from carbohydrate to lipid utilization irrespective of which of the two branches is activated.
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    URL: http://dx.doi.org/10.1007/BF01045816
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    Demonstration of correlations between the 8 and 10 kHz atmospherics and the inflammatory reaction of rats after carrageenan injection (1988)
    Springer
    International journal of biometeorology 32 (1988), S. 201-204 
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    ISSN: 1432-1254
    Keywords: Atmospherics ; Carrageenan inflammation ; Rat ; Susceptibility ; Correlations
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geography , Physics
    Notes: Abstract Between the mean daily density of 28 kHz atmospherics and the onset of epileptic fits there is a highly significant correlation coefficient (r) of 0.30; there is a negative coefficient of −0.20 between the fits and the mean daily density of 10 kHz atmospherics. The onset of heart infarction is correlated with 28 kHz atmospherics (r=0.15). Furthermore, we have discovered that sudden deafness is also correlated with certain configurations of atmospherics. In this paper we report the following correlation coefficients between the inflammatory reaction of rats to a carrageenan injection (rci) into a hind paw and the mean daily pulse rate of atmospherics of the same day:r=0.49 for the 8 kHz atmospherics (P〈0.02) andr=0.44 for the 10 kHz atmospherics (P〈0.04). The correlations between rci reaction and other atmospherics (12 and 28 kHz) are smaller and not significant. By the method of multiple linear regression we found a multipleR=0.54 between rci reaction and the 8 and 10 kHz atmospherics (the regression function for the rci reaction is 0.15+0.004×8 kHz+0.002×10 kHz,P〈0.05).
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    Yeast single copy gene URP1 is a homolog of rat ribosomal protein gene L21 (1993)
    Springer
    Current genetics 23 (1993), S. 15-18 
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    ISSN: 1432-0983
    Keywords: Yeast ; Rat ; Ribosomal protein ; 60S Ribosomal subunit
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary This communication reports on a single-copy gene of Saccharomyces cerevisiae which is homologous to the rat ribosomal protein gene L21. The yeast and the rat genes show 59% identity in DNA sequences and in the predicted protein sequences. This yeast gene is, therefore, assumed to code for an as yet unassigned ribosomal protein (URP1). The URP1 open reading frame is 480 nucleotides long and can encode a protein of about Mr 18 200. Like most of the other known ribosomal protein genes, URP1 is interrupted by an intron in its 5′ terminal part and it is preceeded by upstream sequence elements which usually regulate transcription of these genes. Northern blot analysis reveals that the URP1 gene is actually expressed in vivo.
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    URL: http://dx.doi.org/10.1007/BF00336743
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    Melatonin accelerates reentrainment of the circadian rhythm of its own production after an 8-h advance of the light-dark cycle (1989)
    Springer
    Journal of comparative physiology 166 (1989), S. 97-102 
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    ISSN: 1432-1351
    Keywords: Rat ; Melatonin ; Circadian rhythm ; 5-hydroxytryptophan
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The rhythm in melatonin production in the rat is driven by a circadian rhythm in the pineal N-acetyltransferase (NAT) activity. Rats adapted to an artificial lighting regime of 12 h of light and 12 h of darkness per day were exposed to an 8-h advance of the light-dark regime accomplished by the shortening of one dark period; the effect of melatonin, triazolam and fluoxetine, together with 5-hydroxytryptophan, on the reentrainment of the NAT rhythm was studied. In control rats, the NAT rhythm was abolished during the first 3 cycles following the advance shift. It reappeared during the 4th cycle; however, the phase relationship between the evening rise in activity and the morning decline was still compressed. Melatonin accelerated the NAT rhythm reentrainment. In rats treated chronically with melatonin at the new dark onset, the rhythm had already reappeared during the 3rd cycle, in the middle of the advanced night, and during the 4th cycle, the phase relationship between the evening onset and the morning decline of the NAT activity was the same as before the advance shift. In rats treated chronically with melatonin at the old dark onset or in those treated with melatonin 8 h, 5 h and 2 h after the new dark onset during the 1st, 2nd and 3rd cycle, respectively, following the advance shift, the NAT rhythm reappeared during the 3rd cycle as well but in the last third of the advanced night only. Neither triazolam nor fluoxetine together with 5-hydroxytryptophan administered around the new dark onset facilitated NAT rhythm reentrainment after the 8-h advance of the light-dark cycle.
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    URL: http://dx.doi.org/10.1007/BF00190214
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    Zwei elektronenmikroskopisch unterscheidbare Formen sekundärer sensorischer Endigungen in einer Muskelspindel der Ratte (1970)
    Springer
    Cell & tissue research 110 (1970), S. 97-107 
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    ISSN: 1432-0878
    Keywords: Muscle Spindles ; Different types of sensory endings ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung In einer Muskelspindel der Ratte, die an einer Serie alternierender Semidünn- und Ultradünnquerschnitte untersucht wurde, wurden zwei benachbart an „nuclear chain“-Fasern gelegene Nervenendformationen unterschiedlicher Bauweise festgestellt. Die beiden Endformationen sind mit ein und derselben Nervenfaser der Gruppe II verbunden und daher als Bestandteile einer sekundären sensorischen Endigung zu betrachten. Die Nervenendformation an einer der beiden „nuclear chain“-Fasern hat anulo-spirale Form. Die Nervenendformation an der anderen „nuclear chain“-Faser weist am Querschnittsbild eine Anzahl von Axonen auf, die zwischen Plasmalemm und Basalmembran der intrafusalen Muskelfaser eng aneinanderliegen. Nicht alle Axonquerschnitte stehen in direktem Kontakt mit der intrafusalen Faser. Das terminale Axon scheint sieh nach Eintritt unter die Basalmembran der intrafusalen Faser mehrfach in relativ dünne Äste unregelmäßigen Verlaufs zu teilen. Diese Form der Endigung könnte ein Korrelat der sog. „flower spray“-Endigung im Sinne Ruffinis (1898) darstellen. Die beiden morphologisch unterschiedlichen Endformationen innerhalb der sekundären Endigung gleichen einander und den Endformationen der primären Endigung bezüglich folgender Ultrastrukturmerkmale: 1. Es besteht synaptischer Kontakt zwischen Axon und intrafusaler Muskelfaser (synaptischer Spalt durchschnittlich 200 Å) ohne Zwischenlagerung von Basalmembranmaterial; 2. die terminalen Axonabschnitte liegen direkt unter der Basalmembran der intrafusalen Muskelfaser und sind nicht von Schwannschen Zellen bedeckt; 3. Mangel an synaptischen Bläschen; 4. desmosomenartige Verhaftungen zwischen Zellmembranen von Axon und intrafusaler Faser; 5. dyadenartige Anlagerungen des sarkoplasmatischen Retikulums an die Zellmembran der intrafusalen Faser im Bereich des synaptischen Spaltes. Nach unseren derzeitigen Vorstellungen sprechen diese Ultrastrukturmerkmale für eine rezeptorische Natur der beschriebenen Nervenendigungen.
    Notes: Summary In a rat muscle spindle transversally cut into a series of alternating semithin and ultrathin sections, two different forms of nerve terminations were found on two neighbouring nuclear chain fibres. The two nerve terminations were connected to the same group II nerve fibre and are consequently constituents of one particular secondary sensory ending. The nerve termination on one of the two nuclear chain fibres is of the anulo-spiral type. The nerve termination on the second nuclear chain fibre shows a number of axons lying closely together between plasma membrane and basement membrane of the intrafusal muscle fibre. Not all of these axons are in direct contact with the intrafusal fibre. The terminating nerve fibre seems to be divided into several branches of rather small diameters and irregular courses. It is suggested that this kind of termination could be a correlate of the so-called “flower spray” type of sensory endings in muscle spindles. The two morphologically different nerve terminations in the secondary ending have the following ultrastructural characteristics in common with those of the primary ending: 1) Synaptic contact between axon and intrafusal muscle fibre (synaptic gap about 200 Å) without interposition of basement membrane material; 2) terminal axons located beneath the basement membrane layer of intrafusal muscle fibres without covering by Schwann cells; 3) lack of synaptic vesicles; 4) desmosome-like structures between plasma membranes of axon and intrafusal muscle fibre, and 5) dyads of the sarcoplasmic reticulum adjacent to the synaptic cleft. According to present knowledge these features indicate that all of these endings are sensory ones.
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    On the innervation of the rat and pig adrenal cortex (1971)
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    Cell & tissue research 116 (1971), S. 151-156 
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    ISSN: 1432-0878
    Keywords: Adrenal cortex ; Innervation ; Receptors ; Rat ; Pig
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The innervation of the adrenal cortex of the rat and the pig is investigated with the electron microscope. Nerve fibers containing synaptic and two types of dense-cored vesicles come into contact with endocrine cells. There are no specialized pre- and postsynaptic membranes. The synaptic cleft is about 200 Å wide. Generally the basement membrane between nerve and cell is absent. These observations are discussed on the base of more recent experimental findings. Small fibers having an average diameter of about 0.2 to 0.5 μ and containing only tubules and filaments are considered to represent parts of an afferent nervous system.
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    Histochemical and chemical studies on pre- and postnatal development of the different systems of “short” and “long” adrenergic neurons in peripheral organs of the rat (1971)
    Springer
    Cell & tissue research 116 (1971), S. 319-341 
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    ISSN: 1432-0878
    Keywords: Adrenergic neurons ; “Short” and “long” systems ; Pre- and postnatal development ; Peripheral organs ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The adrenergic innervation in the submaxillary gland, heart, kidney, small intestine, and accessory male genital organs and the development of the adrenal chromaffin cells and the sympathetic ganglia were studied in the rat from 15 days post coitum to 16 days post partum using the fluorescence histochemical method of Falck and Hillarp. The postnatal development of the noradrenaline concentrations in the heart and vas deferens was followed by fluorometric determinations. At about 15 days post coitum, the anlagen of the sympathetic chains were well visible in the form of two dorsal segmented columns of small branching sympathicoblasts exhibiting an intense catecholamine fluorescence. In the midline, ventrally to these two anlagen, another column of sympathicoblasts developed; this seemed to give rise to the prevertebral ganglia and to the short adrenergic neurons supplying the internal genital organs. At the level of the adrenal anlagen, small intensely fluorescent chromaffin cells were collected in two bilateral groups which became enclosed by adreno-cortical cells. This enclosure was, however, not complete even at two weeks post partum. Bundles of growing sympathetic nerves were visible in the periphery of the various organs studied at 19–21 days post coitum. A terminal innervation of the organs suggestive of a functional transmitter mechanism did not start to establish until at or immediately after birth. The final pattern of innervation was usually reached at about one week post partum, and the following development proceeded largely in the form of a quantitative increase in the number of nerves participating in the innervation apparatus. The adult level of noradrenaline in the heart and vas deferens was reached three to five weeks after birth. The small intestine was an exception in that the final pattern of innervation in the wall was attained immediately after birth. There was no overt difference in the rate of development of the terminal sympathetic innervation in organs supplied by short adrenergic neurons (accessory male genital organs) compared to the innervation of the submaxillary gland, heart and kidney, which receive classical long adrenergic neurons.
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    The fine structure of the granulosa cells in the domestic fowl and the rat (1971)
    Springer
    Cell & tissue research 119 (1971), S. 58-67 
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    ISSN: 1432-0878
    Keywords: Ovary ; Rat ; Fowl ; Granulosa cells ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The granulosa cells of the ovarian follicle of the rat and the domestic fowl have been studied with the light and electron microscope. The nuclei of the granulosa cells were irregular with indentations and large in proportion to the cytoplasm of the cell. The mitochondria had a dense, dark matrix with only few cristac. The Golgi apparatus was moderately developed, located towards the oocyte in a juxtanuclear position. The endoplasmic reticulum was rather sparse. Lipid droplets were only occasionally encountered. Microtubules were regularly observed. The functions of the granulosa cells are discussed. Compared with the steroid-producing cells of the theca interna of the same follicles, the granulosa cells primarily are the nursing cells for the growing oocyte and mainly have the characteristics of protein forming cells.
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    Ultrastructural studies on the hypothalamic neurosecretory neurones of the rat (1971)
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    Cell & tissue research 122 (1971), S. 283-300 
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    ISSN: 1432-0878
    Keywords: Paraventricular nucleus ; Rat ; Synthesis of hormones ; Acid phosphatase ; Osmium impregnation ; Neurosecretion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructural features of the paraventricular neurones of the non-treated rat are presented comparing them with those of the supraoptic neurones. No striking differences are seen between the general electron microscopic characteristics of the paraventricular and supraoptic neurones. The importance of adequate fixation to obtain good preservation of the neurones is emphasized, since inadequate fixation can cause e.g. artefactual appearance of “dark neurones”. The previously presented classification of the neurosecretory neurones into two categories (e.g. “light and dark neurones”) on the basis of the number of ribosomes is not considered justifiable, since their number can vary to a very great extent even within a single cell. The synthesis of neurosecretory products in the paraventricular neurones obviously follows the general mode of the synthesis of secretory proteins: ribosomes—RER—Golgi complex—secretory vesicles. On the basis of the localization of heavy metal deposits after osmium impregnation and demonstration of acid phosphatase the Golgi complex of the paraventricular neurones is found to be polarized. The direction of the polarity is discussed. The substructures of the dense cores of the neurosecretory granules and of the contents of the lysosomal dense bodies are nearly identical. Therefore it is considered impossible to determine positively the nature of the dark condensed material within the Golgi complex. The characteristics of the immature neurosecretory granules and the possibility of releasing neurosecretory products into the cytoplasm already within the perikarya are speculated.
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    A two-filament system and interaction of heavy meromyosin (HMM) with thin filaments in smooth muscle (1971)
    Springer
    Cell & tissue research 122 (1971), S. 350-356 
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    ISSN: 1432-0878
    Keywords: Smooth muscle ; Two-filament system ; Small intestine ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The structure of glycerinated smooth muscle from small intestine of adult rat was investigated by electron microscopy. In the central parts of the tissue blocks a two-filament system was found, consisting of parallel thick and thin filaments with regularly spaced interconnections, closely resembling that of striated muscle. In the peripheral parts of the blocks only thin filaments were found. The thin filaments were identified as actin by the formation of arrowhead complexes after incubation with heavy meromyosin.
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    Identification of helical polyribosomes in sections of mature skeletal muscle fibers (1971)
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    Cell & tissue research 121 (1971), S. 531-547 
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    ISSN: 1432-0878
    Keywords: Helical polyribosomes ; Skeletal muscle ; Polysomes ; Levator ani ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The localization and configurations of ribosomes in mature white skeletal muscle fibers of the rat were investigated. Differential visualization of ribosomes and glycogen granules was obtained by fixation with glutaraldehyde only and staining of the sections with uranyl acetate. Ribosomes are then electron dense and glycogen granules electron transparent. Their identity was ascertained by selective extractions of ribonucleic acid and polysaccharide. The vast majority of the ribosomes is not membrane-bound. They are located intermyofibrillarly (predominantly at the level of the I-bands), beneath the sarcolemma, and in the paranuclear cones of sarcoplasm. Occasionally short stretches of granular reticulum occur, often as characteristic double walled vesicles with ribosomes on the inner membrane only. Three main types of polysomal configurations are observed: rosettes of 4 to 6 ribosomes, helical arrays, and whorls of up to about 25 probably membrane-bound ribosomes. The average number of ribosomes in the extended helical configurations is estimated to be about 60. It is argued that these helices represent the polysomes instrumental in the synthesis of the large subunits of myosin. It is emphasized that helical polyribosomes are by no means typical of striated muscle, but probably represent a common configuration of large free polysomes.
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    Immersion and perfusion fixed rat adrenal medulla: The problem of mixed cells, clear cells, and the mode of secretion (1972)
    Springer
    Cell & tissue research 126 (1972), S. 261-277 
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    ISSN: 1432-0878
    Keywords: Adrenal medulla ; Rat ; Cell types ; Secretion ; Influence of fixation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Das Nebennierenmark der Ratte wurde nach Anwendung verschiedener Fixationsmethoden untersucht. Nach Immersionsfixation mit Glutaraldehyd oder Osmiumtetroxyd finden sich in der Nebenniere sog. Mischzellen, helle Zellen, syncytiale oder plasmodiale Zellen, die von den Untersuchern als Artefaktbildungen angesehen werden. In allen Proben nach Perfusionsfixation wurden solche Artefaktbildungen niemals beobachtet. Bei Immersionsfixation wurde eine enge Beziehung zwischen Sekretgranula und Cytoplasmamembran beobachtet, was bei Perfusionsfixation selten der Fall war. Die heutigen Theorien über den Sekretionsmechanismus bei Nebennierenmarkzellen werden aufgrund der vorgelegten Ergebnisse diskutiert. Die Arbeit zeigt die wesentlichen Vorteile der Anwendung der Perfusionsfixation für die Untersuchung der Nebenniere.
    Notes: Summary The adrenal medulla of the rat was studied utilizing various methods of fixation. In adrenal medulla specimens after immersion fixation either with glutaraldehyde or osmium tetroxide, elements such as mixed, clear, syncytial, or plasmodial cells, believed to be of artifactual origin, are observed in all of this material examined. These elements are absent in the specimens prepared by perfusion fixation. In specimens prepared by immersion fixation, secretory granules are found in close proximity to the plasma membrane; this localization is infrequent after perfusion fixation. Current theories of the mechanism of secretion of adrenal medullary hormones are discussed on the basis of our results. This investigation demonstrates the advantage and necessity of perfusion fixation in the study of the adrenal medulla.
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    The fine structure of macrophages in the enamel organ, with special reference to the microtubular system (1972)
    Springer
    Cell & tissue research 126 (1972), S. 466-482 
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    ISSN: 1432-0878
    Keywords: Macrophages ; Microtubules ; Enamel organ ; Rat ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In the enamel organ of rat incisors macrophages are present in the zone of matrix formation, the transitional zone, the enamel maturation and pigmentation zone. The macrophages accumulate adjacent to redifferentiating amelocytes in the transitional zone. The macrophages phagocytize fragments of disintegrating amelocytes. In addition to the well known complement of organelles the macrophages present an elaborated microtubular system, scattered, thick filaments, a cortical feltwork of thin filaments, and spherical nuclear bodies. The microtubules emanate from “attached” and free pericentriolar satellites and radiate aster-like towards the cell surface or into pseudopods or curve along the nuclear surface for long distances, often related to nuclear constrictions. It is suggested that the microtubular system plays a prominent role in directional movement of the macrophages. The cortical filaments, if contractile, may create the cytoplasmic flow necessary for the cell motility.
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    An electron microscopic study of the normal synaptic relationships and early degenerative changes in the rat olfactory tubercle (1972)
    Springer
    Cell & tissue research 127 (1972), S. 462-482 
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    ISSN: 1432-0878
    Keywords: Olfactory tubercle ; Rat ; Degeneration ; Synapse
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The olfactory tubercle of the rat was studied by electron microscopy both in the normal and after ipsilateral olfactory bulb ablation at survival times of from 14 hours to seven days. Particular emphasis was placed on synaptic structures and their changes following the lesion. Normal synapses are similar to those described in previous studies and presynaptic profiles are of at least three types. Types-A and -B contain round vesicles and form asymmetrical contacts and type-C profiles contain flattened vesicles and form symmetrical contacts. There appear to be two major types of degenerative changes. The electron-lucent type predominates at early survival times and is seen first at 14 hours. These profiles show an early reduction in numbers of vesicles with mitochondrial swelling followed by shrinkage of the profile. These profiles become increasingly electron-dense at later survival times. The second major type of degenerating profile is initially electron-dense. The earliest changes in these profiles are an increased axoplasmic density and increased microtubular density and clumping without apparent loss of vesicles. These profiles also become progressively more electron-dense at longer survival times. The observations are discussed in relation to previous reports.
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    Intercellular bridges and division patterns of rat spermatogonia (1972)
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    Cell & tissue research 127 (1972), S. 201-208 
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    ISSN: 1432-0878
    Keywords: Spermatogenesis ; Rat ; Mitosis ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The pattern of intercellular cytoplasmic bridges between rat spermatogonia and between spermatocytes is illustrated from electron microscopy of serial sections. Clones, or syncytia, containing as many as 22 connected spermatogonia and as many as 74 connected spermatocytes were observed. The absence of closed rings of cells agrees with the observation that intercellular bridges are the result of incomplete cell division, rather than cell fusion. The bridges thus are a record of spermatogonial divisions within a clone. In early spermatogonial generations there is a predominantly linear arrangement. The groups of spermatocytes have more side branches. From the presence of synaptonemal complexes it is concluded that the connected spermatocytes of a given clone are in about the same developmental stage. The pattern of intercellular bridges indicates, however, that not all nuclei in a clone undergo mitosis in the same cycle. The connected cells of a clone are therefore not all of the same generation. From unconnected bridges it is assumed that new clones originate from single cells or groups of spermatogonia which separate from an existing clone.
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    Contractility and structure of adult rat seminiferous tubules in organ culture (1972)
    Springer
    Cell & tissue research 130 (1972), S. 171-179 
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    ISSN: 1432-0878
    Keywords: Tubuli seminiferi ; Rat ; Structure ; Contractility ; Organ culture
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Isolated pieces of seminiferous tubules of adult rats were grown in organ culture for up to 8 weeks in Petri dishes on the surface of nutrient agar. The medium consisted of newborn calf serum, Eagle's minimum essential medium, glutamate and antibiotics. This method allowed observation of the contractions of the seminiferous tubules in the culture. Contractility, light and electron microscopic structure and histochemically demonstrable activities of alkaline phosphatase and ATPase of the tubule walls were studied at 1-week intervals. The contractility and alkaline phosphatase activity were maintained in the tubule wall for 3 weeks, and the activity of ATPase was maintained for 5 weeks. The thin filaments of the myoid cells, which are responsible for the contractility, were seen with the electron microscope in tubules cultured for 5 weeks. The organ culture method described in the present paper seems to be valuable for studies concerning the functioning of the myoid cells of the seminiferous tubules and the possibility that this is regulated by hormones.
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    URL: http://dx.doi.org/10.1007/BF00306955
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    Ultrastructural evidence for exocytosis in the median eminence of the rat (1972)
    Springer
    Cell & tissue research 131 (1972), S. 99-107 
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    ISSN: 1432-0878
    Keywords: Median eminence ; Rat ; Exocytosis ; Micro-pinocytosis ; Releasing factors
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Exocytosis has been demonstrated by electron microscopy in the external zone of the median eminence of the rat. Exocytotic profiles have been observed in nerve fibres characterized by the presence of granular vesicles with median diameters of 90–103 nm and agranular vesicles of about 50 nm. In addition to the small agranular vesicles, coated vesicles of the same size have been found in many nerve fibres, suggesting that at least part of the agranular vesicles in the median eminence originate by micro-pinocytosis. The nature of the fibres showing exocytosis is discussed. Attention is drawn to the possibility of identifying types of fibres in the median eminence by the occurrence of exocytosis.
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    URL: http://dx.doi.org/10.1007/BF00307203
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    Form und Verteilung subependymaler Basalmembranlabyrinthe am Ventrikelsystem der Ratte (1972)
    Springer
    Cell & tissue research 132 (1972), S. 553-562 
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    ISSN: 1432-0878
    Keywords: Basement membrane ; Brain ventricles ; Rat ; Subependymal labyrinths ; Light- and electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Mit der Perjodsäure-Bisulfit-Aldehydthionin-Färbung (Specht) lassen sich am ganzen Ventrikelsystem des Rattengehirns sub- und interependymale Strukturen lichtmikroskopisch nachweisen, die elektronenmikroskopisch als Basalmembranlabyrinthe (BML) identifiziert werden können. Verschiedene Formen dieser BML lassen sich unterscheiden. Sie stehen in Verbindung mit subependymalen Kapillaren. Die Verteilung der BML wird in Ventrikelkarten dokumentiert.
    Notes: Summary Sub- und interependymal structures, being demonstrable by a period-acid-bisulfit-aldehydthionine-method (Specht), occur in the whole ventricular system by light microscopy. They can be identified electron microscopically as basement membrane labyrinths (BML). Different shapes of these BML can be distinguished. They are in communication with the basement membrane of subependymal capillaries. The distribution of BML is documented in “ventricular maps”.
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    Ultrastructural studies on the hypothalamic neurosecretory neurons of the rat (1972)
    Springer
    Cell & tissue research 134 (1972), S. 205-225 
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    ISSN: 1432-0878
    Keywords: Diabetes insipidus ; Rat ; Hypothalamo-neurohypophysial system ; Synthesis of hormones ; Light- and Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The general ultrastructural features of the hypothalamo-neurohypophysial system in rats with hereditary hypothalamic diabetes insipidus (DI-rats, Brattleboro strain) are described. There is no decisively distinguishing difference between the neurons of the supraoptic and paraventricular nuclei. The neurons of both nuclei show signs of active protein synthesis. The perikarya of the neurons are markedly hypertrophic, the nuclei are large and the nucleoli prominent. In the cytoplasm there are numerous ribosomes, abundant rough-surfaced endoplasmic reticulum and extensive Golgi complexes. However, very few neurosecretory granules are to be seen. The axons of the hypothalamo-neurohypophysial tract are likewise enlarged and the paucity of neurosecretory granules is a striking feature also in the area of the tract. The majority of nerve endings in the posterior pituitary of DI-rats are devoid of neurosecretory granules. Microvesicles are abundant in the nerve endings and there are findings which suggest that microvesicles are involved either in endoor exocytosis. The signs of active protein synthesis and the concomitant paucity of neurosecretory granules are interpreted to imply transportation of the secretory proteins in an extragranular phase. The possible mode of release of the secretory proteins from the nerve endings and the role of microvesicles therein are discussed.
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    URL: http://dx.doi.org/10.1007/BF00307154
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    On the fine structure of the perivascular cells in the neural lobe of rats (1972)
    Springer
    Cell & tissue research 132 (1972), S. 25-34 
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    ISSN: 1432-0878
    Keywords: Neurohypophysis ; Rat ; Perivascular cells ; Neurosecretion ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The purpose of this study is to investigate the ultrastructural features of perivascular cells as found in the neural lobe of the hypophysis. In particular, an inquiry was made into the nature of the relationship of such cells to neurosecretory fibers and endings. The latter, in fact, are often invaginated within the perivascular cells and enveloped by their processes; furthermore, they often reveal a certain number of empty granules as well as characteristics of degenerative nature. In the course of this study the localization of the perivascular cells has been investigated as well as that of their processes within the extensive interlobular network typical of the hypophysial neural lobe of rodents. Based on the data gathered, the hypothesis is put forward that the perivascular cells play an important role in the turnover of neurosecretory endings, both under physiological and experimental conditions, contributing thereby to the release of post-hypophysial hormones.
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    URL: http://dx.doi.org/10.1007/BF00310294
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    Elektronenmikroskopische Untersuchungen zur funktionellen Morphologie des Tubero-hypophysären Systems der Ratte (1973)
    Springer
    Cell & tissue research 139 (1973), S. 101-148 
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    ISSN: 1432-0878
    Keywords: Infundibulum ; Rat ; Neuro-glial synapses ; Neuro-Vascular contacts ; Corticotropin-Releasing Factor ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung 1. Die Gefäßfortsätze von ependymalen und subependymalen Zellen bilden in der subependymalen Zone und in der Zona interna des Ratteninfundibulum mit Nervenfasern kompakte neuro-gliöse Faserbündel, die sich in der Zona externa aufzweigen. 2. In allen Zonen des Infundibulum kommen zwischen den Nervenfasern und den Gefäßfortsätzen zahlreiche neuro-gliöse Synapsen vor. In den Gefäßfortsätzen fällt die hohe Zahl an Mikrotubuli sowie die zahlreichen, vielgestaltigen Einschlüsse auf. 3. In der subependymalen Zone sind die Interzellularspalten an bestimmten Stellen außerordentlich weit. Sie haben eine kanalartige Beschaffenheit und enthalten feine Bündel von Nervenfasern. 4. Von den lateralen Anteilen des Infundibulum her erreichen Dendriten von Ganglienzellen des Nucleus infundibularis die Mitte des Infundibulum. In dieser Region sind axodendritische Synapsen anzutreffen. 5. Morphometrische Analysen der Nervenfaserendigungen der Zona externa von Normaltieren zeigen, daß die prozentuale Verteilung der nach Granulagröße differenzierten Nervenfaserklassen für Mitte und Seite der Zona externa etwa gleich ist. Zwischen der Größe der Elementargranula und der Anschnittfläche der zugehörigen Nervenfasern besteht eine direkte Beziehung. 6. Die Nervenfaserendigungen erreichen die Basalmembran des perikapillären Raumes fast ausschließlich im Bereich von gefäßwärts gerichteten Vorwölbungen der Zona externa. Das Ausmaß, in dem Nervenfasern im Vergleich zu den Gefäßfortsätzen von Ependymund Gliazellen den perivaskulären Raum erreichen, ist medial weitaus größer als lateral. 7. Bei bilateral adrenalektomierten Ratten nimmt in bestimmten, vorwiegend lateral gelegenen Nervenfasern die Zahl und Größe der Elementargranula in Abhängigkeit von der Überlebensdauer zu. Dies dürfte auf eine verstärkte Synthese und Speicherung von Corticotropin-Releasing Factor in diesen Nervenfasern zurückzuführen sein. Gegenüber dem Normalbefund ist die neurohämale Kontaktfläche erheblich vergrößert. Der perivaskuläre Raum enthält zerfallene Nervenfaserteile, die durch Bindegewebszellen phagocytiert werden. Diese Veränderungen dürften durch eine unter Versuchsbedingungen verstärkte Wachstumstendenz der Nervenfasern in Richtung auf die Blutgefäße und durch eine Abschnürung der Nerven-faserendigungen ausgelöst werden.
    Notes: Summary 1. In the subependymal and internal zones of the rat median eminence nerve fibres and vascular processes of ependymal and subependymal cells form neuro-glial bundles. They branch in the external zone. 2. In all these three zones of the infundibulum numerous neuro-glial synapses are found between nerve fibres and vascular processes of glial cells. The vascular processes contain a high number of microtubules as well as polymorphous granular inclusions. 3. In certain regions of the subependymal layer the intercellular spaces are enlarged. They form channel-like spaces containing small bundles of delicate nerve fibres. 4. Nerve cells of the infundibular nucleus located in the lateral parts of the infundibulum send dendrites to the medial parts of the infundibulum. In this area axo-dendritic synapses are found. 5. For morphometric analysis, the nerve fibres of the external zone were classified according to the diameter of their granules. It is shown that in the different regions of the external zone the distribution of the various types of nerve fibre is similar. Moreover it can be seen that a direct correlation exists between the size of the sectional plane of a given nerve fibre and the size of the granules it comprises. 6. Nerve fibre endings abutting on the basement membrane of the pericapillary space are mostly found in bulb-like protrusions of the external zone. The extent to which nerve fibres reach the perivascular space—as compared with the vascular processes of ependymal and glial cells—is higher in the medial than in the lateral parts of the infundibulum. 7. In bilaterally adrenalectomized rats the number and diameter of elementary granules increases in nerve fibres located laterally. This increase is directly related to the survival time and may be due to an enhanced synthesis and storage of Corticotropin-Releasing Factor in these nerve fibres. Compared with the findings in untreated animals the neurohemal contact area is significantly enlarged. The perivascular space contains degenerating nerve fibres which are undergoing phagocytosis by connective tissue cells. It is assumed that these alterations are due to the increased growth of nerve fibres towards the vessels of the “Mantelplexus”, and that, following adrenalectomy, this excessive growth leads to a pinching off of nerve fibres.
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    The adrenergic innervation of the renal artery and vein of the rat (1973)
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    Cell & tissue research 138 (1973), S. 261-272 
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    ISSN: 1432-0878
    Keywords: Extrarenal blood vessels ; Rat ; Adrenergic nerves ; Fluorescence microscopy ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The adrenergic innervation of the extrarenal blood vessels of the rat left kidney was investigated by fluorescence histochemistry and by electron microscopy. The trunk of the renal artery proximal to the aorta is elastic and appears to be very sparsely innervated. In contrast, near the kidney the renal artery—which divides into 3 to 4 large branches of the muscular type possesses a dense adrenergic innervation. The adrenergic terminal axons are situated in the adventitia close to the external elastic lamella, but only rarely in close contact with smooth muscle cells. In most instances several terminal axons are grouped and enclosed by a Schwann cell, single axons being rare. All terminal axons are able to take up and to store 5-hydroxydopamine which strongly suggests that they are adrenergic. The innervation of the renal vein is more sparse than that of the muscular arteries but somewhat denser than that of the elastic artery. In addition, close to the origin of the renal artery the presence of “small intensively fluorescent” (SIF) cells as well as of some adrenergic ganglion cells is noted. The latter are situated in the adrenergic nonterminal axon bundles, which run parallel to the blood vessels. It is concluded that the uneven adrenergic innervation along the artery as well as individual variations in the branching of the artery are the main causes of the unusually high individual variations of the NA content of this organ such as used in pharmacological experiments.
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    Modifications des cellules gonadotropes de la préhypophyse chez la ratte injectée de testostérone au cours du cycle oestral (1973)
    Springer
    Cell & tissue research 138 (1973), S. 63-73 
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    ISSN: 1432-0878
    Keywords: Adenohypophysis ; Rat ; Gonadotrophic cells ; Cycle, influence of testosterone ; Light microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary 4-day cyclic adult female Wistar rats were injected subcutaneously with testosterone propionate on diestrus 1 at 16:00 and on diestrus 2 at 10:00 respectively. Non-injected females served as controls. Autopsy was performed on diestrus 2 at 23:00, and on proestrus at 14:00 and 17:00 respectively. The blue Alcian-PAS staining was used to evidence FSH (β) and LH (γ) pituitary cells. In control animals and in diestrus 2 injected females only a small number of FSH cells could be detected on diestrus 2 at 23:00. This number increased markedly on proestrus at 14:00 and decreased on proestrus at 17:00. A similar evolution was observed in diestrus 1 testosterone injected females, but the number of FSH cells appeared higher at any stage of autopsy in these females than in diestrus 2 injected females and in control rats. In control females, numerous LH cells were observed on diestrus 2 at 23:00. The number of these cells was diminished on proestrus at 14:00 and still more at 17:00. On the contrary few LH cells were detected in testosterone injected females on the evening of diestrus 2. An increase of these cells occurred on proestrus at 14:00, followed at 17:00 by only a weak diminution as established by comparison with control animals. An inhibition of FSH release and a suppression of the proestrus surge of LH were therefore supposed to cause, on one hand, the slowing up of follicular growth observed in diestrus 1 injected females and, on the other hand, the blockage of ovulation noted in both diestrus 1 and diestrus 2 treated animals.
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    Intracellular pathways of receptor-bound GnRH agonist in pituitary gonadotropes (1985)
    Springer
    Cell & tissue research 239 (1985), S. 3-8 
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    ISSN: 1432-0878
    Keywords: GnRH receptors ; Gonadotropes ; Coated pits ; Internalization ; High-resolution autoradiography ; LHRH, Gonadoliberin ; Pituitary gland ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Localization of GnRH receptors in rat pituitary gonadotropes was studied by use of 125I-[azidobenzoyl-D-Lys6]GnRH which, upon photolysis, is covalently bound to the receptor molecule. Using high resolution autoradiography, it was found that, after a 90-min incubation of the analog with pituitary cells at 4° C, 93% of the silver grains were associated with the plasma membrane of the gonadotropes. After 45-min incubation of the cells at 37° C, clustering and internalization of the receptor-bound GnRH analog were evident. Silver grains were associated with coated pits, intracellular vesicles, Golgi complexes, lysosome-like structures and secretory granules. The data indicate that receptor-bound GnRH agonist is internalized, at least in part, via coated pits and is subsequently routed to lysosomes where degradation of the hormone-receptor complex may occur. The presence of a considerable amount of silver grains associated with secretory granules may suggest that some of the internalized receptor molecules can escape degradation and be recycled to the cell membrane.
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    Distribution pattern of drained antigens and antibodies in the subcapsular sinus of the lymph node of the rat (1985)
    Springer
    Cell & tissue research 239 (1985), S. 31-35 
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    ISSN: 1432-0878
    Keywords: Lymph filtration ; Antigen and antibody distribution ; Subcapsular sinus ; Lymph node ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A recent study of lymph nodes of the rat showed that they are morphologically and physiologically compartmentalized. A compartment of a node includes a portion of subcapsular sinus into which the lymph, entering via the related afferent lymphatic opening, is filtered. The study also showed that colloidal carbon injected locally in a small dose becomes predominantly associated with the areas of the inner wall of the subcapsular sinus that cover the extrafollicular zone of the peripheral cortex. Little carbon is seen over the folliculo-nodules (follicles with a nodule or germinal center). The question arose as to whether drained natural substances, as antigens and antibodies, follow the same pattern of distribution in the subcapsular sinus as the carbon. Therefore, small doses of fluorescein isothyocyanate (FITC)-conjugated antigens were injected locally into normal rats whose own antibodies in the nodes were stained by immunofluorescence. The pattern of distribution of the antigens in the draining nodes was found to be the same as that of the carbon. Furthermore, the lymph-carried antibodies of the rats were found to follow the same pattern. The morphological basis for such a pattern is explained. The results are further discussed with regard to the probable normal entry route of lymph-carried antigens in the parenchyma of nodes.
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    Evidence for tight junctions between odontoblasts in the rat incisor (1985)
    Springer
    Cell & tissue research 239 (1985), S. 137-140 
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    ISSN: 1432-0878
    Keywords: Lanthanum ; Odontoblasts ; Tight junctions ; Tooth pulp ; Ultrastructure ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Odontoblasts are known to be involved in the process of dentinogenesis but it is not clear whether substances may also be deposited in predentine and dentine by passing between these cells. Although tight junctions have been described, it is not clear if they are macular or “leaky” as opposed to continuous or “tight”. In this study use has been made of the permeability of fenestrated capillaries amongst the odontoblasts to deposit the penetrative tracer lanthanum in the interodontoblastic space. This was done by perfusion of anaesthetized rats with physiological solutions containing lanthanum nitrate at 37° C. Immersion fixation of transverse segments of mandibular incisors and examination with an electron microscope showed that lanthanum could permeate 40–50 μm between the odontoblasts to reach the peripheral pulp. Towards the predentine, often less than 10 μm from the capillaries, its progress was abruptly and completely halted by the junctions at the apical ends of the odontoblast cell bodies. Lanthanum was not found in the predentine. The mature secretory odontoblasts in the rat incisor have therefore been shown to be joined by continuous tight junctions. In the process of dentinogenesis this means that all substances deposited in predentine and dentine must arrive by passing through the odontoblasts.
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    Fenestrations of the basal lamina of intestinal villi of the rat (1985)
    Springer
    Cell & tissue research 239 (1985), S. 183-188 
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    ISSN: 1432-0878
    Keywords: Fenestrations ; Basal lamina ; Intestine, small ; Immune system ; SEM ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Fenestrations of the basal lamina of rat intestinal villi were revealed by scanning electron microscopy after removal of the overlying epithelial cells by osmic acid maceration. These fenestrations are circular to oval in shape and are 0.5 μm to 5 μm in diameter. They are richly distributed at a density of 1–2x104/mm2 in the upper two thirds of the villi, except at the very tips. Roughly 500 fenestrations are found on each side of an average sized tongue-shaped villus. Transmission electron-microscopic observations showed that these fenestrations were passages for migrating cells of the immune system such as lymphocytes, eosinophils and macrophages. Protrusions from the basal parts of epithelial cells were also observed passing through these fenestrations. These findings are discussed with respect to their immunological implications and to the passage of nutrients.
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    Fine structure of the lysosomes in the two types of synoviocytes of normal rat synovial membrane (1985)
    Springer
    Cell & tissue research 239 (1985), S. 293-298 
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    ISSN: 1432-0878
    Keywords: Acid phosphatase cytochemistry ; Lysosomes ; Synovial membrane ; Synoviocytes ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The lysosomal system of the two types of synoviocytes (A and S) from the knee joint of normal rat synovial membrane was studied by electron-microscopic acid phosphatase cytochemistry. In random sections of the synovial intima lysosomes were more often encountered in the A-cell profiles than in the S-cell profiles. Characteristically, type-A synoviocytes showed many large and medium-sized lysosomes the cytochemical appearance of which varied considerably. No acid phosphatase activity was detectable in the cisternae of the Golgi apparatus or in the Golgi vesicles. In type-S synoviocytes the lysosomes were smaller, and more uniform in cytochemical appearance. Heavy deposits of acid phosphatase reaction product were constantly demonstrated in cisternae of the Golgi apparatus as well as in smooth-walled Golgi vesicles in type-S cells. The findings that type-A and type-S synoviocytes show distinctly different organization of the lysosomal system indicate that the roles of the lysosomes in these two types of cells may be different.
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    Ultrastructural features of rat pituicytes in organotypic culture (1973)
    Springer
    Cell & tissue research 143 (1973), S. 107-116 
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    ISSN: 1432-0878
    Keywords: Neurohypophysis ; Rat ; Pituicytes ; Organotypic culture ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Neural lobes of adult rats have been explanted and organ-cultured for 5–10 days. While perivascular cells and neurosecretory fibers undergo a progressive degeneration, scattered pituicyte-like cells are observed mostly associated with each other in number of two or three cells for group. Cultured pituicytes are quite similar to in vivo pituicytes except for some particular features as the shape of the nucleus and the number of dense bodies. Furthermore they share with the in vivo pituicytes the phagocytic capacity which appears even increased as far as neurosecretory fibers are concerned. Finally, degenerating pituicytes and free lipid droplets are observed in the intercellular spaces: the significance of these facts is discussed and tentatively interpreted. The organotypic culture of the neural lobe seems to represent an experimental model useful to obtain a relatively pure population of pituicytes.
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    New types of endoplasmic reticulum in neurons of the paracervical ganglion of the rat (1973)
    Springer
    Cell & tissue research 143 (1973), S. 505-515 
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    ISSN: 1432-0878
    Keywords: Endoplasmic reticulum ; Paracervical ganglion (Rat) ; Neurosecretion ; Electron microscopy ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Two new types of structure of the cytoplasm of an autonomic neuron were described: (1) Inclusions of the rough ergastoplasmic reticulum, which were named “ergastosomes”, contain finely granular material with moderately electron opaque staining with both glutaraldehyde-OsO4 and KMnO4 fixations. A short comment was made on the nature of the contents of the ergastosomes. (2) Tubular formations of endoplasmic reticulum were found in the axons and/or dendrites of the paracervical ganglion.
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    Electron microscopic study of rat pituitary primordium in organ culture (1973)
    Springer
    Cell & tissue research 146 (1973), S. 453-461 
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    ISSN: 1432-0878
    Keywords: Hypophysis ; Primordium ; Rat ; Organ culture ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary To see whether adenohypophysial tissue has the capacity of self-differentiation, Rathke's pouch together with part of the neurohypophysial primordium was isolated from 12-(Group A), 14- (Group B) and 15-day-old (Group C) rat fetuses and cultivated for 9, 6 and 5 days, respectively. Electron microscopic examination of these explants showed many adenohypophysial cells containing electron dense granules, indicative of cytodifferentiation in all groups. Three cell types were distinguishable on the basis of the size of their granules. Variable amounts of neurohypophysial tissue were seen in some explants of Groups B and C, but not A. This “pars nervosa” contained pituicytes with lipid-like inclusions in their cytoplasm but no neurosecretory axons. The adenohypophysial cells abutting on the pars nervosa were arranged rather regularly like cells of the pars intermedia which contained a few granules of about 200 mμ diameter. From these data it is concluded that in rats granule formation in the adenohypophysial primordial cells starts in the absence of hypothalamic neurosecretory substances. It is uncertain from this study whether these cells actually contain hypophysial hormones.
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    In vitro analysis of the cellular localization of luteinizing hormone releasing factor (LRF) in the basal hypothalamus of the rat (1974)
    Springer
    Cell & tissue research 149 (1974), S. 371-378 
    Details
    ISSN: 1432-0878
    Keywords: LRF ; Hypothalamic localization ; Rat ; Ependyma ; Glia ; Light and electron microscopic Autoradiography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Light and electron microscopic autoradiographic analysis of the medial basal hypothalamus of rat brains incubated for 30 and 60 minutes in tritiated luteinizing releasing factor (3H-LRF) revealed selective uptake in the form of silver grains over specialized ependyma (tanycytes) and perivascular glial cells in the palisade-contact zone of the median eminence. The functional capacity of tanycytes and glia are discussed in light of these data.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00226771
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    The ultrastructure of the duct system in the rat extraorbital lacrimal gland (1973)
    Springer
    Cell & tissue research 144 (1973), S. 453-466 
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    ISSN: 1432-0878
    Keywords: Lacrimal gland ; Rat ; Duct system ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The duct system of the rat exorbital lacrimal gland consists of intercalated ducts, interlobular ducts and excretory ducts. The morphological changes from one type of duct to the next are gradual. At the light microscopical level this consists of a change from a bilaminar epithelium in the intercalated ducts to an epithelium, consisting of approximately three layers — which may be pseudostratified — in the excretory ducts. The basal layer of the intercalated ducts consists of myoepithelial cells, whereas the inner epithelial cells may have both a secretory and an electrolyte transporting function. The interlobular duct epithelium contains many cells with deep infoldings of the basolateral plasma membranes and associated mitochondria, suggesting a similar function to the striated duct epithelium in salivary glands. Numerous basal cells in this epithelium have tentatively been interpreted as unusual myoepithelial cells. Nerve terminals have been observed in the ductal epithelium.
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    URL: http://dx.doi.org/10.1007/BF00307373
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    Failure to demonstrate serotonergic neurons in the myenteric plexus of the rat (1974)
    Springer
    Cell & tissue research 150 (1974), S. 493-496 
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    ISSN: 1432-0878
    Keywords: Serotonin ; Neurotransmitter ; Myenteric plexus ; Rat ; Histofluorescence
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Several recent studies suggested that serotonergic neuron-like elements are present in the guinea pig ileum. The present paper reports an extensive study of the digestive tract of the rat with the use of a histofluorescence technique. Administration of the serotonin precursor, tryptophan, associated with a monoamine oxidase inhibitor, did not allow histochemical demonstration of rapidly fading, yellow fluorescent, 6-hydroxydopamine-resistant neurons; conversely such neurons were readily detected in the brain. It is concluded that serotonergic neuron-like elements cannot be detected histochemically in the rat myenteric plexus area after chemical sympathectomy.
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    URL: http://dx.doi.org/10.1007/BF00225972
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    Studies on the juxtaglomerular apparatus (1974)
    Springer
    Cell & tissue research 151 (1974), S. 457-469 
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    ISSN: 1432-0878
    Keywords: Juxtaglomerular apparatus ; Rat ; Adrenalectomy ; Renin and secretory granules ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Die Reaktion des juxtaglomerulären Apparates auf Adrenalektomie wurde untersucht. Im Stadium der Nebenniereninsuffizienz, sechs Tage nach der Operation, wurde quantitativ morphometrisch eine Abnahme der Volumendichte der Sekretgranula (von 32% auf 16%) festgestellt. Golgi-Apparat und Ergastoplasma proliferieren stark, wobei insbesondere die erweiterten Cisternen des Ergastoplasmas auffallen.
    Notes: Summary The response of the Juxtaglomerular apparatus to bilateral adrenalectomy was studied in rats. After the sixth postoperative day, symptoms of severe adrenal insufficiency had developed. In the Juxtaglomerular cells, the volume density of the secretory granules decreased from 32% to 16%. The Golgi apparatus and rough endoplasmic reticulum underwent considerable proliferation, the latter showing strikingly enlarged cisternae.
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    URL: http://dx.doi.org/10.1007/BF00222991
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    Sex differences in adrenocortical structure and function (1974)
    Springer
    Cell & tissue research 151 (1974), S. 525-536 
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    ISSN: 1432-0878
    Keywords: Adrenal cortex ; Rat ; Sex differences ; Gonadal hormones ; Karyometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Adrenal glands of adult female rats are heavier than the glands of corresponding male rats. Postpubertal orchiectomy increases the adrenal weight, an effect restored by testosterone replacement. Under the same conditions ovariectomy of 8 weeks duration does not change the adrenal weight while estradiol replacement enhances the relative adrenal weight. Karyometric studies have shown that nuclei in the female zona fasciculata cells are larger (app. 18%) than those of the male. Similar but only slight differences (2%) were observed in the zona reticularis. Orchiectomy results in enlargement of cell nuclei within all zones of the adrenal cortex; testosterone replacement has the opposite effect. Ovariectomy of 8 weeks duration slightly enhances the volume of nuclei of the zona glomerulosa cells, has no effect on the nuclei of the zona fasciculata and reduces the volume of nuclei in the zona reticularis. Estradiol replacement reduces the volume of nuclei of the zona glomerulosa cells but increases nuclear volume in the zona fasciculata and in the zona reticularis. Thus testosterone has an inhibitory effect on the adrenal cortex of the rat while the physiologic effect of estradiol on the morphology of this gland, particularly on the zona fasciculata cells is rather dubious. The author wishes to thank Mrs. B. Westerska and Miss K. Siejak for excellent technical assistance.
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    URL: http://dx.doi.org/10.1007/BF00222997
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    Sex differences in adrenocortical structure and function (1974)
    Springer
    Cell & tissue research 151 (1974), S. 537-547 
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    ISSN: 1432-0878
    Keywords: Adrenal cortex ; Rat ; Sex differences ; Gonadal hormone ; Stereologic studies
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Adult female rats have heavier adrenals than males. Orchiectomy increases the adrenal weight, an effect reversed by testosterone. Neither ovariectomy nor estradiol replacement has an effect on absolute adrenal weight. The stereologic analysis of the volume fractions of particular adrenocortical zones have shown that the volume fraction of the zona glomerulosa in females is smaller as compared with males. On the contrary, the volume fractions of the fasciculata and reticularis zones are higher in female than in male rats. In both sexes gonadectomy and gonadal hormone replacement has an effect on the volume fractions of particular adrenocortical zones, these changes being more pronounced due to orchiectomy or testosterone replacement. The adrenal cortex of all experimental groups contains a similar quantity of parenchymal cells. The cytoplasm volume of a single adrenocortical cell is higher in all zones of the female adrenals as compared with the male. Orchiectomy increases the volume of the cytoplasm in fasciculata and reticularis cells. This effect was reversed by testosterone. Neither ovariectomy nor estradiol replacement has an effect on the volume of the cytoplasm in the fasciculata and reticularis cells. These studies have shown that sex differences with regards to rat adrenal size and weight depend upon the “physiologic atrophy” of the male adrenal cortex, while neither ovariectomy (8 weeks after operation) nor estradiol replacement has a conspicuous effect on the morphologic changes of this gland.
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    URL: http://dx.doi.org/10.1007/BF00222998
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    Increased gap junctional area in the rat liver after administration of dibutyryl cAMP (1985)
    Springer
    Cell & tissue research 239 (1985), S. 651-655 
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    ISSN: 1432-0878
    Keywords: Gap junctions ; cAMP ; Liver ; Freeze-fracturing ; Morphometry ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Since cAMP has recently been reported to be a possible physiological modulator of cell-to-cell communication, we performed a quantitative freeze-fracture investigation on the hepatocyte gap junctions after administration of a membrane-permeant derivative of this cyclic nucleotide. For this purpose, male rats received two intraperitoneal injections of 100 mg dibutyryl cAMP/kg body weight with a time interval of 2.5 h. Litter mates were injected with saline only. Five hours after the start of the treatment, tissue blocks of the left lateral liver lobe were fixed by immersion and processed for freeze-fracture. By point counting on negatives projected on a square double-lattice test system the relative gap junctional area on contiguous hepatocyte membranes was determined. As compared to control animals, the proportion of the membrane area occupied by gap junctions in dibutyryl cAMP-treated liver parenchyma significantly increased from 4.9% to 6.1%. Within the gap junctions no changes in shape, particle density or packing pattern were observed. Possibly, the enlarged gap junctional area provides structural pathways for the integration of the response of hepatocytes to messages mediated by cAMP.
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    URL: http://dx.doi.org/10.1007/BF00219244
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    Quantitative data on the fine structural organization of the palisade zone of the median eminence (1973)
    Springer
    Cell & tissue research 136 (1973), S. 111-120 
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    ISSN: 1432-0878
    Keywords: Median eminence ; Rat ; Granular vesicles ; Ultrastructure ; Quantitative evaluation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In order to characterize different sub-zones in the palisade zone of the rat median eminence, quantitative ultrastructural parameters were applied to brains fixed in aldehyde-osmium tetroxide. The palisade zone has been subdivided in 4 successive sub-zones. Increasing numbers of granular vesicles (GV), especially those smaller than 110 nm, are observed from dorsal to ventral sub-zones. There also are more GV per unit area of nervous tissue in the perivascular than in the more dorsal sub-zones. The individual nerve profiles exhibit a larger size in the perivascular layer than in the more dorsal areas, whereas the number and size of nerve profiles devoid of vesicles diminish from dorsal to ventral. As a consequence more GV occur in the perivascular nerve profiles. In the GV containing nerve profiles the concentration of GV is, however, constant in the different sub-zones. A fluctuating size of the preterminal and terminal parts of the nerve fibres is suggested.
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    URL: http://dx.doi.org/10.1007/BF00307683
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    Ultrastructural changes in rat epididymis after vasectomy (1973)
    Springer
    Cell & tissue research 136 (1973), S. 177-182 
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    ISSN: 1432-0878
    Keywords: Rat ; Epididymis ; Effect of vasectomy ; Spermatozoa ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Epididymal biopsies from rats that had undergone unilateral or bilateral vasectomies from one to eight months previously were compared with biopsies from their contralateral side or from normal controls to ascertain what ultrastructural changes had occurred. After vasectomy, spermatozoa appeared to dissolve in the lumen of the caput epididymidis and to be absorbed by the principal cells. About 5 weeks after vasectomy, numerous lamellar accumulations became apparent in the supernuclear region. Their resemblance to lysosomes or residual bodies was confirmed by an acid phosphatase reaction. After 10 weeks, similar lamellar and polymorphic accumulations on the contralateral side of animals with unilateral vasectomies indicated that resorption had also increased on the unligated side.
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    URL: http://dx.doi.org/10.1007/BF00307438
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    A radioautographic study of the transport of 125I-labeled serum lipoproteins in rat aorta (1973)
    Springer
    Cell & tissue research 138 (1973), S. 223-237 
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    ISSN: 1432-0878
    Keywords: Aorta, endothelium ; Rat ; Transport of serum lipoproteins ; Radioautography ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The transport of 125I-labeled serum lipoproteins through the aortic endothelium was studied by radioautography. Rat aorta and heart was perfused in vitro with a medium containing human very low density (VLDL), low density (LDL), high density lipoprotein (HDL), delipidated HDL apolipoprotein or rat HDL. In all lipoproteins more than 95% of the radioactivity was TCA precipitable and lipid radioactivity was from 2–4% in HDL, 4–6% in LDL, 7–15% in VLDL. After 18–60 min of perfusion and wash with unlabeled medium, most of the aortic radioactivity was TCA precipitable and the percent of lipid counts was similar to that in the original lipoprotein. Following perfusion with VLDL, LDL, or HDL the radioautographic reaction was seen over the endothelium, the subendothelial space and the inner media, and was separated by an unlabeled zone from the reaction present over the adventitia. Uniform labeling of the entire wall was found after perfusion with HDL apolipoprotein. The presence of silver grains over endothelial cells in regions rich in plasmalemmal vesicles suggested that these organelles participate in the transport of the labeled lipoprotein, as was shown for lactoperoxidase (Stein and Stein, 1972). The present data indicate that cholesterol may enter the aortic wall as a constituent of lipoprotein particles. Since an HDL particle carries less than 1/20 of the cholesterol present in a LDL particle, it seems that the lower susceptibility of the female to atheromatosis might be related to the higher ratio of HDL to LDL particles in the female serum.
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    URL: http://dx.doi.org/10.1007/BF00306609
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    Tagesrhythmische Veränderungen im Granulationsindex der juxtaglomerulären Zellen der Rattenniere (1973)
    Springer
    Cell & tissue research 137 (1973), S. 141-143 
    Details
    ISSN: 1432-0878
    Keywords: Juxtaglomerular cells ; Rat ; Granulation index ; Diurnal rhythm ; Statistical evaluation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Das Granulations-Index der juxtaglomerulären epitheloiden Zellen der Rattenniere unterliegt tagesrhythmischen Schwankungen, wobei die berechneten Werte in den Nachtstunden significant höher sind als in den Tagesstunden.
    Notes: Summary Marked diurnal changes occur in the granulation index of the juxtaglomerular cells in the rat kidney. According to the results the night values are significantly higher than those obtained in daytime.
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    URL: http://dx.doi.org/10.1007/BF00307054
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    Suppression of somatotrophs in growth hormone injected rats (1973)
    Springer
    Cell & tissue research 140 (1973), S. 309-314 
    Details
    ISSN: 1432-0878
    Keywords: Pituitary Gland ; Rat ; Somatotropin ; Cellular Response ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The response of somatotrophs to large doses of purified bovine growth hormone was examined in uninephrectomized rats drinking 1% sodium chloride in an attempt to prolong the action of the hormone. Growth hormone produced a triphasic response in the ultrastructure of somatotrophs. Uninephrectomy and salt alone induced no changes in somatotrophs as compared to unoperated animals consuming tap water. In the first phase (3 days) the cross sectional area of the cell increased, the size of the largest granule per cell as well as the number of granules per cell increased significantly. All these parameters then reached control level after 7 days of injections during a second phase. Suppression of somatotrophs by exogenous growth hormone was evident by 16 days (third phase) when the area of the cell, the size of the largest secretory granule as well as the number of granules per cell all decreased significantly. Somatotrophs apparently did not react to suppression by a lysosomal mechanism inasmuch as no increase in the number of lysosome-derived structures was seen even at 16 days.
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    URL: http://dx.doi.org/10.1007/BF00307020
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    Vascular permeability to lanthanum in the rat incisor pulp (1985)
    Springer
    Cell & tissue research 239 (1985), S. 131-136 
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    ISSN: 1432-0878
    Keywords: Capillary permeability ; Lanthanum ; Peripheral nerves ; Tooth pulp ; Ultrastructure ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Experiments were performed to compare the permeability of capillaries supplying the endoneurial environment, which is invested by perineurium, with vascular permeability in the pulp where perineurium is absent. Anaesthetised rats were perfused through the aorta with physiological solutions containing lanthanum nitrate at 37° C. Pieces of inferior alveolar nerve and segments of mandibular incisors were immersion-fixed and transverse sections were examined electron microscopically for the distribution of lanthanum. In the pulp the nerve fibres pass between lanthanum-impermeable arterioles and venules en route to the incisal end. In the peripheral pulp a few capillaries were permeable but the most permeable capillaries lay between the odontoblasts. Pulpal capillary permeability was attributed to the fenestrated endothelium and contrasted with the unfenestrated endoneurial capillaries which were impermeable to lanthanum. Whereas the tight junctions of endoneurial capillaries are known to prevent certain blood-borne substances from entering the endoneurium, it was not clear whether the permeability of the pulpal capillaries, which are distant from the nerve fibres, could affect the nerve fibre environment. No extravasated lanthanum reached the pulpal nerve fibres suggesting that they are not affected. Technically it was not possible to examine the incisal third of the tooth where the situation could be different because the volume of the pulp decreases and capillaries lie closer to the nerve fibres.
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    Origin and distribution of neuropeptide Y-, vasoactive intestinal polypeptide- and substance P-containing nerve fibers in the urinary bladder of the rat (1985)
    Springer
    Cell & tissue research 239 (1985), S. 141-146 
    Details
    ISSN: 1432-0878
    Keywords: Neuropeptides ; Autonomic denervation ; Neuropeptide Y ; Vasoactive intestinal polypeptide (VIP) ; Substance P ; Urinary bladder ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The origin and distribution in the urinary bladder of nerve fibers containing neuropeptide Y (NPY), vasoactive intestinal polypeptide (VIP) and substance P (SP) were investigated in rats. Experimental procedures comprised preganglionic decentralization or postganglionic denervation of the bladder and also chemical sympathectomy as well as capsaicin treatment of newborn rats. Nerve fibers containing NPY were richly distributed in the detrusor muscle and also in the pelvic ganglia. Numerous NPY-containing nerve cell bodies were found in pelvic ganglia. A rich occurrence of VIP fibers and a more sparse distribution of SP-containing fibers were also found in the bladder as well as a relatively rich representation of VIP- containing nerve cell bodies in the pelvic ganglia. After decentralization the intensity of VIP and NPY immunofluorescence increased in nerve cell bodies of the pelvic ganglia and in nerve fibers in the wall of the bladder. Postganglionic denervation, on the other hand, eliminated all peptides examined in the bladder wall. After postganglionic denervation the situation in the ganglia was approximately the same as after decentralization. Chemical sympathectomy (6-OHDA) did not seem to change significantly the frequency and distribution of VIP-, SP- and NPY-fibers in the muscle layer of the bladder or in the pelvic ganglia, while the NPY-containing nerve fibers in the submucosal layer and around blood vessels of the bladder disappeared. Adrenergic nerve fibers in the wall of the bladder (visualized by histofluorescence) were markedly reduced in number after administration of 6-OHDA. Capsaicin-treatment of newborn rats caused a loss of SP-fibers in the wall of the bladder, supporting the view that these fibers are sensory in nature in the urinary bladder. Although it cannot be entirely excluded that NPY-containing fibers in the wall of the bladder are adrenergic, the present results suggest that the NPY-fibers as well as the VIP-fibers of the bladder wall originate mainly in non-adrenergic cell bodies of the pelvic ganglia. However, perivascular NPY-containing nerve fibers are adrenergic in nature.
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    Non-lymphoid cells of bronchus-associated lymphoid tissue of the rat in situ and in suspension (1985)
    Springer
    Cell & tissue research 239 (1985), S. 177-182 
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    ISSN: 1432-0878
    Keywords: Lymphoid tissue ; Lung ; Bronchi ; Immuno-histochemistry ; Enzyme histochemistry ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Immunohistochemical, enzyme-histochemical and electron-microscopical methods were used to study non-lymphoid cells of control and stimulated rat bronchus associated lymphoid tissue (BALT) in situ and in suspensions. Particular attention was paid to the so-called antigenhandling cells, i.e., the interdigitating cells (IDC), which are situated in the T-cell areas, the follicular dendritic cells (FDC), which appear to be restricted to germinal centers, and macrophages, present both in T-cell and B-cell areas. The interdigitating cells were distinguished by being Ia-positive and by the presence of acid phosphatase and non-specific esterase activity in an area near the nucleus. Follicular dendritic cells could be observed in situ by using a monoclonal antibody and by the in vitro trapping of HRP-anti-HRP complexes. Several types of macrophages were found. At the electron-microscopical level no well-developed IDC and FDC could be detected in control BALT. However, in BALT of lipopolysaccharide-stimulated and mycoplasma-infected rats, well-developed IDC and FDC were found. It can be concluded that IDC's and FDC's can be found in BALT.
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    Stimulatory effect of follicle-stimulating hormone on rat Leydig cells (1985)
    Springer
    Cell & tissue research 239 (1985), S. 405-415 
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    ISSN: 1432-0878
    Keywords: Testis ; Leydig cell ; FSH ; Morphometry ; Ultrastructure ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The effects of FSH on the testicular interstitial tissue of immature hypophysectomized rats were studied by comparing morphological changes in Leydig cells with quantitative changes in interstitial tissue histology using morphometric analysis. Three groups of rats received subcutaneous injections of 0.5 ml saline vehicle or 10 μg rFSH or 20 ng oLH (equivalent to the amount of LH known to contaminate the FSH), twice daily for 7 days. Administration of FSH significantly increased testis weight and stimulated more advanced spermatogenesis compared to saline or LH. Morphometric analysis of testes of LH-treated rats showed a small but significant increase in total interstitial cell volume compared to saline treatment. FSH caused much greater increases in the total volume of interstitial tissue and interstitial cells than either saline or LH and significantly increased the total volume of interstitial fluid by comparison with the other groups. FSH but not saline or LH treatment resulted in a striking hypertrophy of Leydig cells, to produce cells ultrastructurally identical to Leydig cells from adults. Since the target tissue of FSH is the seminiferous epithelium, the observed effects on Leydig cells by FSH treatment suggest that the secretion of factors by the seminiferous tubules may mediate the maturation of Leydig cells.
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    URL: http://dx.doi.org/10.1007/BF00218021
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    Microthread-like filaments connecting the epithelial basal lamina with underlying fibrillar components of the connective tissue in the rat trachea (1985)
    Springer
    Cell & tissue research 239 (1985), S. 485-495 
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    ISSN: 1432-0878
    Keywords: Trachea ; Basal lamina ; Anchoring fibril ; Ruthenium red-positive filaments ; New anchoring device ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The structural relationship between the basal lamina and the underlying reticular tissue was studied, with special attention to the relationship among basal lamina-associated anchoring fibrillar (AF) arcs (Kawanami et al. 1978, 1979) and other fibrillar components, in the epithelium-denuded trachea of the rat. Quantitative analysis of a large number of AF arcs reveals that the majority of the AF arcs has no other fibrillar components of passage. This suggests that most AF arcs do not serve as a real anchoring device, connecting the basal lamina with the underlying reticular tissue, as has so far been suggested by Kawanami et al. (1978). Ruthenium-red staining reveals the presence of a unique meshwork of microthread-like filaments connecting the undersurface of the basal lamina or the AF arcs with the underlying fibrillar components with a remarkable continuity, suggesting that the filaments act as a real anchoring device; these filaments link, instead of the AF arcs, the basal lamina, to the subjacent reticular tissue. Various enzymatic treatments of the filaments indicate that their chemical nature is probably non-collagenous (glyco)protein without glycosaminoglycan moieties.
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    URL: http://dx.doi.org/10.1007/BF00219226
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    Karyometrische Untersuchungen am Nucleus suprachiasmaticus geblendeter Ratten (1973)
    Springer
    Cell & tissue research 143 (1973), S. 143-147 
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    ISSN: 1432-0878
    Keywords: Rat ; Suprachiasmatic nucleus ; Blinding ; Retinohypothalamic connections ; Karyometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Radioaktiv markierte Aminosäuren werden bei Säugetieren nach intraokulärer Injektion nicht nur zu den primären optischen Kerngebieten, sondern auch in den Nucleus suprachiasmaticus des Hypothalamus transportiert (Moore und Lenn, 1972; Hendrickson, Wagoner und Cowan, 1972; Moore, 1973). Dieser Befund macht eine direkte Verknüpfung zwischen der Netzhaut und dem sekretorisch aktiven Nucleus suprachiasmaticus wahrscheinlich, obwohl mit Silbertechniken eine solche Verbindung nicht sicher nachgewiesen werden konnte. Karyometrische Studien am Nucleus suprachiasmaticus männlicher Wistar-Ratten zeigen 6 Tage nach beidseitiger Blendung eine signifikante Abnahme der Zellkerndurchmesser. Dieses Ergebnis spricht für eine Aktivitätsänderung der Neurone im Nucleus suprachiasmaticus geblendeter Ratten.
    Notes: Summary Intraocular injection of labeled amino acids results, in different mammals, in an accumulation of radioactive material not only in the primary optic centers but also within the hypothalamic suprachiasmatic nucleus (Moore et al., 1972; Hendrickson et al., 1972; Moore, 1973). This finding argues in favour of a direct connection between the retina and the secretory suprachiasmatic nucleus although silver techniques do not show such a pathway. In male Wistar rats the nuclear diameter of the suprachiasmatic neurons decreases significantly 6 days after bilateral experimental ablation of the retina. These results indicate an alteration in activity of the suprachiasmatic neurons in blinded rats.
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    Influence de la méthode de fixation sur l'observation des divisions cellulaires dans l'adénohypophyse du rat mâle (1973)
    Springer
    Cell & tissue research 143 (1973), S. 535-547 
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    ISSN: 1432-0878
    Keywords: Adenohypophysis ; Rat ; Mitoses, topographic distribution ; Influence of fixation ; Light microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé Les mitoses de l'adénohypophyse du rat mâle ont été examinées comparativement après fixation par perfusion et après fixation par immersion. Après fixation par perfusion la répartition topographique des mitoses dans le parenchyme est homogène, et l'index mitotique est de 1,85 pour 1 000 cellules. Après fixation par immersion, la densité des mitoses décroit de la périphérie vers le centre, et l'index mitotique n'est que de 0,80 mitoses pour 1 000 cellules. La lenteur de pénétration du fixateur pendant l'immersion est tenue pour principal responsable des différences observées. Elle entraîne une modification de l'aspect des mitoses, telle que plus de la moitié d'entre elles ne sont pas identifiables et échappent aux comptages.
    Notes: Summary The mitoses of the adenohypophysis in male rats have been observed comparatively after fixation by perfusion and fixation by immersion. After fixation by perfusion, the topographic distribution of mitoses throughout the parenchyma is homogenous and the mitotic index is 1.85 for 1 000 cells. After fixation by immersion, the density of the mitoses is decreasing from the periphery towards the center and the mitotic index is only 0.80 for 1 000 cells. The slow penetration of the fixative during fixation by immersion is considered to be the main cause in the differences observed. This slow action causes a modification in the aspect of the mitoses, and more than fifty percent of them cannot be identified and escape to the counts.
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    Ultrastructural investigations of the palisade-shaped nerve fiber terminals of the normal hairs of rat's snout (1974)
    Springer
    Cell & tissue research 147 (1974), S. 259-269 
    Details
    ISSN: 1432-0878
    Keywords: Nerve endings ; Hair ; Rat ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Palisade-shaped nerve endings of the small normal hairs of the rat snout were examined with the electron microscope (fixation by perfusion). The terminals are located inside the ‘glassy membrane’ in the area of the neck of the hair root. The 10–20 radially arranged terminal axons are in direct contact with the basement membrane of the epithelium of the external root sheath. The axons are surrounded on all sides by leaf-shaped processes of the Schwann cells. The surfaces of these cell processes are marked by numerous vesicle-like invaginations (approx. 1000 Å dia.). Transverse sections from several areas of the palisadeshaped nerve endings are compared with longitudinal sections. In the upper area ‘empty’ vesicles (approx. 500–600 Å in diameter) occur, along with electron-dense vesicles (approx. 800–1100 Å in diameter); in the middle area, the axons are distended and contain accumulations of mitochondria.
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    The parietal layer of bowman's capsule in experimental hypertension (1974)
    Springer
    Cell & tissue research 147 (1974), S. 183-190 
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    ISSN: 1432-0878
    Keywords: Kidney ; Rat ; Bowman's capsule ; Experimental hypertension
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The parietal layer of Bowman's capsule was examined in the rat in control animals and in animals made hypertensive by treatment with desoxycorticosterone acetatesaline and by clipping of the renal artery. At an early stage of elevation of blood pressure and, occasionally, prior to elevation of blood pressure, the epithelial cells of this layer showed basal cytoplasmic protrusion and reduplication accompanied by an increase in the thickness of the basement membrane. These changes preceded evidence of glomerular or renal arteriolar pathology. They presumably reflect either a response of this layer to increased blood pressure and modified glomerular function, or a direct effect of the factors that also induces blood pressure elevation. In either case, they imply a greater functional significance for the parietal layer than has usually been attributed to it.
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    The ultrastructure of the accessory sex organs of the male rat (1974)
    Springer
    Cell & tissue research 148 (1974), S. 57-67 
    Details
    ISSN: 1432-0878
    Keywords: Prostate ; Rat ; Cyproterone ; Alterations ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The dorsal lobe and the coagulating gland of the rat prostate were studied after administration of the anti-androgenic compound Cyp A for varying periods (7–20 days). There was a general involution of the organs with macroscopic atrophy and reduced amount of secretory material. Ultrastructurally the cells were pale, contained less organelles as compared with the controls, loss of cytoplasm and reduction both of cell height and width. The major changes also included reduction of the Golgi area, the rough endoplasmic reticulum and the number of free ribosomes. Within the dorsal lobe prominent nuclear changes were found, comprising different types of intranuclear inclusions of membranous configurations. The alterations observed in the present study are similar to the changes which were found in castrated animals and are consistent with atrophy. The results are discussed in relation to the available biochemical and autoradiographic data on the different lobes.
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    Elementary granules, small vesicles and exocytosis in the rat neurohypophysis after acute haemorrhage (1972)
    Springer
    Cell & tissue research 125 (1972), S. 277-288 
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    ISSN: 1432-0878
    Keywords: Neurohypophysis ; Rat ; Exocytosis ; Freeze-etching ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Neural lobes of rats subjected to severe acute haemorrhage under sodium pentobarbitone anaesthesia were examined electron microscopically and the ultrastructure compared with that in anaesthetised and unanaesthetised controls. Changes in the localisation and numerical distribution of elementary granules and small vesicles in the neurohypophysial nerve endings of bled rats were consistent with the occurrence of exocytosis. The occurrence of “exocytotic profiles” was observed more frequently in freeze-etched tissue samples as compared with the material fixed for conventional electron microscopy. The ratio of small vesicles: elementary granules was shown to be significantly increased (P〈0.005) in the nerve endings of neural lobes from bled rats. Equally, the numbers of exocytotic profiles related to 1000 μm2 of neurohypophysial tissue area were significantly greater (P〈0.005) in bled rats.
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    Extracellular perivascular connective tissue space in the medial terminal nucleus of the accessory optic system in rats (1972)
    Springer
    Cell & tissue research 125 (1972), S. 289-294 
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    ISSN: 1432-0878
    Keywords: Accessory optic system ; Rat ; Blood vessels ; Extracellular space ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Two types of capillaries were found in the medial terminal nucleus of the rat accessory optic system. Type one capillaries are surrounded by glial processes and lack a perivascular space, whereas the type two capillaries and arterioles show a distinct extracellular perivascular space often filled with collagen fibrils. An internal as well as an external basal lamina lines these spaces. No fenestration of the endothelium was observed.
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    Further studies on synaptic junctions (1972)
    Springer
    Cell & tissue research 125 (1972), S. 415-431 
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    ISSN: 1432-0878
    Keywords: Synapses ; Rat ; Cerebral cortex ; Glutaraldehyde/E-PTA ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Synaptic junctions in intact rat cerebral cortex have been examined following glutaraldehyde fixation and phosphotungstic acid (PTA) staining. In the presynaptic ending the network has a hexagonal arrangement, while the dense projections are regularly placed along the presynaptic membrane. Cleft densities occupy the intracleft region. The postsynaptic thickening extends uninterrupted along the length of the junction. Qualitatively, the majority of junctions fall into the ‘discontinuous-continuous’ category, in which the internal coat of the presynaptic membrane together with its associated dense projections is discontinuous along the length of the junction, whereas the postsynaptic thickening is continuous. By contrast, a small number of junctions are ‘continuous-continuous’. In an attempt to analyze the junctions quantitatively, nine indices were measured. Histograms of the size distributions of seven of these appear to be bimodal, and from this it is concluded that two junction populations may be distinguishable on quantitative grounds. It is also shown that the distance separating dense projections at the presynaptic membrane is of the order of 10–15 nm. This surprisingly low value has consequences for current ideas on the relationship between synaptic vesicles and dense projections, and these are discussed at length.
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    URL: http://dx.doi.org/10.1007/BF00306651
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    Die Feinstruktur der interstitiellen Grundsubstanz im inneren Nierenmark der Ratte bei verschiedenen Fixierungsarten (1972)
    Springer
    Cell & tissue research 125 (1972), S. 404-414 
    Details
    ISSN: 1432-0878
    Keywords: Renal medulla ; Rat ; Interstitial ground substance ; Fixation ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Das Interstitium des inneren Nierenmarkes von Ratten wurde nach Anwendung verschiedener Fixierungsarten und Versuchsanordnungen elektronenmikroskopisch untersucht. Neben Bindegewebszellen und kollagenen Fibrillen enthält der interstitielle Raum bandförmige, basalmembranartige Strukturen, in deren weiträumigen Maschen zwei weitere Komponenten, nämlich ein feingranuläres und feinfilamentäres Material sowie kontrastreiche, globuläre Partikel liegen. Diese beiden Formelemente stellen sich bei den verschiedenen Fixierungsarten und Versuchsanordnungen unterschiedlich dar. Bei der feingranulären und feinfilamentären Komponente handelt es sich wahrscheinlich um interstitielles Blutplasma. Diese Deutung wird gestützt durch die morphologische Ähnlichkeit mit dem Blutplasma der Blutgefäße, die unterschiedliche Darstellbarkeit nach Glutardialdehyd-und Formalinfixierung sowie durch die Befunde nach Gefäßperfusion und Nierenvenenstauung. Das Verhalten der globulären Partikel nach OsO4-Einwirkung steht in Einklang mit der schon früher gegebenen Interpretation als präzipitierte saure Mukopolysaccharide. Ihr elektronenoptisches Bild wird im Vergleich zur bekannten makromolekularen Struktur der Mukopolysaccharid-Protein-Moleküle diskutiert.
    Notes: Summary The interstitial ground substance in the inner medulla of the rat kidney is examined electron microscopically after fixation with various fixation agents and under different experimental conditions. The papillary interstitium contains besides interstitial cells and few collagen fibrils basement membrane like material and two other components, fine granular-fibrillar elements and globular particles with heavy contrast. The appearance of the two latter interstitial components varies according to the different fixation agents used and to the experimental conditions. The fine granular and fine fibrillar material surrounds the globular particles numerously after glutardialdehyde-fixation but scarcely after formaldehyde-fixation. It increases after renal vein occlusion, but is diminished or absent, if the kidney is rinsed bloodfree. These results allow to conclude that this material represents interstitial bloodplasma. The behaviour of the globular particles after OsO4-fixation agrees well with the earlier interpretation according to which they represent precipitated acid mucopolysaccharides. Their electron microscopic appearance is discussed in comparison with the known macromolecular structure of the acid mucopolysaccharides.
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    Further studies on synaptic junctions (1972)
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    Cell & tissue research 125 (1972), S. 432-447 
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    ISSN: 1432-0878
    Keywords: Synaptosomes ; Synapses ; Rat ; Cerebral cortex ; Glutaraldehyde/E-PTA
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Working with glutaraldehyde fixed, PTA stained rat cerebral cortex, the authors compared the ultrastructural features of synaptosomes with those of intact synaptic junctions. In general there is close correspondence between the two, although the cleft densities and postsynaptic focal densities of synaptosomes show a greater degree of focalization than their counterparts in synaptic junctions. The dense projections have similar profiles in both preparations, but are more difficult to distinguish clearly in synaptosomes on account of the closer packing of the presynaptic network around their apices. The limiting membrane of the presynaptic terminal is usually visible in synaptosomes, but not in synaptic junctions. Comparing the preparations quantitatively reinforces the qualitative findings, and points to their overall similarity. However a number of the indices in synaptosomes are significantly smaller than the corresponding ones in synaptic junctions, and this points to the operation of a shrinkage factor during fractionation procedures. This is confined to the pre- and post-synaptic components and does not affect the intervening contact region. Histograms of the size distributions of the indices are similar to those obtained for intact synaptic junctions, the majority displaying two peaks. It is concluded that synaptosomes accurately reproduce the major ultrastructural features of synaptic junctions.
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    On the fine structure of alteration of the adrenal cortex in hypophysectomized rats (1972)
    Springer
    Cell & tissue research 125 (1972), S. 480-496 
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    ISSN: 1432-0878
    Keywords: Adrenal cortex ; Rat ; Normal ; Hypophysectomy ; Structural alteration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The adrenal cortex of normal and hypophysectomized rats was observed by electron microscopy 5–90 days after the operation and, chiefly, the degeneration mechanism of the cortical tissue was discussed. In normal rats mitochondrial inner structures are generally tubular in shape in glomerulosa cells, vesicular (and tubulo-vesicular) in fasciculate cells and tubulo-vesicular (and vesicular) in reticularis cells. Some mitochondria in a few glomerulosa cells show long straight tubular crests in normal as well as hypophysectomized rats. Usually lipid droplets in normal glomerulosa, fasciculate and reticularis cells are surrounded by elements of smooth endoplasmic reticulum, which are very closely associated with mitochondria. About 10–25 days after hypophysectomy, most mitochondria in fasciculate and reticularis cells show tubular crests, and numerous electron lucent lipid droplets are accumulated in these cells. These droplets occupy most parts of the cytoplasm and are sometimes in contact with one another or with mitochondria. The elements of smooth endoplasmic reticulum and Golgi apparatus are markedly reduced in number and size. About 10–90 days after the hypophysectomy, the degenerative cortical cells containing irregularly shaped nuclei, heterogeneously dense bodies in various sizes, and a large number of electron lucent lipid droplets are seen. The author speculates that most fasciculate and reticularis cells degenerate because of a disorder in the lipid metabolism, since ACTH release, which is necessary for synthesis of corticosteroid hormones from cholesterol, is absent in hypophysectomy. The fatty degeneration of the fasciculate and reticularis cells is considered to be a main cause for attenuation of the cortical tissue. Sometimes atrophied cortical cells without lipid droplets are also found 60–90 days after hypophysectomy.
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    The ultrastructure of the accessory sex organs of the male rat (1973)
    Springer
    Cell & tissue research 144 (1973), S. 167-178 
    Details
    ISSN: 1432-0878
    Keywords: Prostate ; Rat ; Castration ; Alterations ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ventral, lateral and dorsal lobes of the rat prostate were studied 2, 3, 5, 7 and 21 days after castration. The major changes were a general reduction of the Golgi area and the RER. The cells became pale and contained less organelles compared with the normals. One of the most conspicuous changes were enormous autophagic vacuoles which were present already after 2 days, seemed to reach a numerical peak 3 days after castration and were seldom encountered after 7 days. Increased number of dense bodies were found within the same period. Lipid droplets were observed in the basal cytoplasm of the epithelial cells, especially in the ventral lobe. The basal cells showed the same involution as in the ordinary epithelium. In addition, macrophages were relatively numerous, and between the epithelial cells also lymphocytes were found. The results are discussed in relation to biochemical data on the different lobes.
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    The ultrastructure of the accessory sex organs of the male rat (1973)
    Springer
    Cell & tissue research 144 (1973), S. 179-189 
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    ISSN: 1432-0878
    Keywords: Seminal vesicles ; Coagulating Gland ; Rat ; Castration ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The seminal vesicles and the coagulating gland of the rat were studied 2, 3, 5, 7 and 21 days after castration. The major changes within the seminal vesicles were primarily formation of whorls of the rough endoplasmic reticulum (RER), followed by a general atrophy with a numerical reduction of the RER-profiles, and with general simplification of the cytoplasm due to loss of the organelles. It was a gradually reduction of secretion granules, diminution of the Golgi apparatus, formation of pigment bodies and autophagic vacuoles. Lipid droplets were observed in the basal cytoplasm of the epithelial cells. In the coagulating gland, similar changes occurred within the Golgi area and the lysosome complex. On the other hand, cisternae of the basal endoplasmic reticulum tended to persist in many cells. The similarity in response strongly suggests that the pathogenetic mechanisms are similar in both organs, i.e. atrophy due to deprivation of the androgenic stimulus. The deprivation of androgen gave rise to an inflammatory-like process with infiltration of lymphocytes and macrophages. The increased number of macrophages may indicate that they contribute in some way to the involution of the prostate by removing the material in the autophagic vacuoles.
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    Ultrastructure of mucosal mast cells in normal and compound 48/80-treated rats (1974)
    Springer
    Cell & tissue research 150 (1974), S. 95-105 
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    ISSN: 1432-0878
    Keywords: Mucosal mast cells ; Rat ; Compound 48/80 ; Degranulation, Release ; Light microscopy ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Mast cells in the tongue and lamina propria of the duodenal mucosa, representing two cell types with different morphological, histochemical and functional properties have been studied under the electron microscope. Both cell types were found to contain similar moderately electron dense and homogeneous granules surrounded by a tight membrane constituting the basic ultrastructural characteristics of mast cells. The mucosal mast cells, however, contained fewer granules per cell and the individual granules often exhibited considerable variation in size. In addition the mucosal mast cells, unlike those of the tongue, peritoneum and skin, had a smooth plasma membrane lacking microvilli and possessed irregularly shaped or lobulated nuclei. In the tongue mast cells, administration of Compound 48/80 caused the formation of vacuoles around the granules, expulsion of granules from the cells and disintegration of the granular matrix, but no changes that could be attributed to 48/80 could be found in the mucosal mast cells.
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    Kinetics of gametogenesis (1974)
    Springer
    Cell & tissue research 154 (1974), S. 443-470 
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    ISSN: 1432-0878
    Keywords: Oocytes and T-prospermatogonia ; Rat ; Quantitative analysis ; Autoradiography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Bei der Ratte findet die sexuelle Differenzierung der Gonade zwischen dem 14. und 15. Tag post conceptionem (p.c.) statt. Während dieser Zeit teilen sich die Oogonien und deren Parallelpopulation—die M-prospermatogonien (multiplying prospermatogonia) oder I-Gonocyten—sehr häufig. Um den 17. Tag p.c. tritt die letzte Generation der Oogonien bzw. der M-prospermatogonien in die Mitose. Die Mitosen bilden häufig “synchronisierte Gruppen”. Die postmitotischen Kerne ihrer Tochterzellen—der Oocyten und der T 1 prospermatogonien (primary transitional prospermatogonia) oder II-Gonocyten—sind klein. Ihr Chromatin ist in Form gröberer Schollen der Kernmembran angelagert. Auf diese Weise kommt das typische “krustenförmige” Aussehen bzw. die Ähnlichkeit mit den Prophasen der Oogonien und M-prospermatogonien zustande. Die Oocyten durchlaufen zunächst die G1-phase (etwa 10 Std Dauer) und treten dann—am Ende des Präleptotänstadiums—in die S-phase. Dann passieren sie die verschiedenen Stadien der meiotischen Prophase und treten vom 3. Tag post partum (p.p.) ab in das Dictyotänstadium. Die T1-prospermatogonien hingegen befinden sich etwa 10 Tage lang in der G1-phase, ohne wesentliche morphologische Veränderungen aufzuweisen. Vom 4. Tag p.p. an durchlaufen sie die S-Phase. Die S-Phasen-Dauer (D-S) beider Zellarten beträgt 11.5 Std und wurde durch Doppelmarkierung mit 14C- und 3H-Thymidin bestimmt. Als am besten geeignete Termine für die Bestimmung der D-S erwiesen sich bei den Oocyten der 18. Tag p.c. und bei den T1-prospermatogonien der 5. Tag p.p. Zu diesen beiden Zeitpunkten war die Anzahl der in die S-phase ein-und austretenden Oocyten bzw. T1-prospermatogonien gleich, die Zellen in S-phase befanden sich im “steady state”. Das Kernvolumen der Oogonien und M-prospermatogonien ist etwa doppelt so groß wie das der postmitotischen Oocyten und T1-prospermatogonien. Bis zum 5. Tage p.p. nimmt das Kernvolumen der Oocyten und T1-prospermatogonien um etwa das Fünffache zu. Der Degenerationsindex der Oocyten liegt wesentlich höher als der der T1-prospermatogonien; er ist postnatal besonders hoch. Aus den T1-prospermatogonien gehen am 4. und 5. Tage p.p. durch Teilung die T 2-prospermatogonien (secondary transitional prospermatogonia) hervor. Die Kerne dieses Zelltyps sind etwas kleiner also die der T1-prospermatogonien. Die T2-prospermatogonien treten am 6. Tage p.p. in die Mitose; es entstehen die ersten A-spermatogonien.
    Notes: Summary In the rat (Wistar-WU) sexual differentiation of the gonads occurs between days 14 and 15 post conception (p.c.). At this time the oogonia and their parallel population — the M-prospermatogonia (I-gonocytes)—divide rapidly. On about day 17 p.c., the last generation of oogonia and M-prospermatogonia, frequently arranged in synchronized clusters, enters mitosis. The postmitotic nuclei of their daughter cells—oocytes and T 1-prospermatogonia (II-gonocytes)—are small; coarse flakes of chromatin are associated with the nuclear membrane causing the typical “crustlike” appearance and the similarity with the prophases of oogonia and M-prospermatogonia. After the oocytes have passed a G1-phase of approximately 10 hr, they enter the S-phase at the end of the preleptotene stage. Then they pass the different stages of the meiotic prophase until they enter the dictyate stage from 3 day post partum (p.p.) onwards. The T1-prospermatogonia, on the other hand, spend a long G1-phase of about 10 days without any conspicuous morphological change before entering the S-phase from day 4 p.p. onwards. The duration of the S-pbase (D-S) of both cell types—oocytes and T1-prospermatogonia—as determined by the double labeling method with 14C- and 3H-thymidine is found to be 11.5 hr. The most favourable time for determining the D-S was day 18 p.c. for the oocytes and day 5 p.p. for the T1-prospermatogonia. On these two days the balance was reached between the cells entering and leaving the S-phase. The nuclear volumes of the postmitotic oocytes and T1-prospermatogonia are approximately half the size of those of their precursors. Until day 5 p.p. the nuclear volumes of the oocytes and T1-prospermatogonia increase about fivefold. The degeneration index of the oocytes is considerably higher than that of the T1-prospermatogonia; postnatally it is especially high. T 2 prospermatogonia arise by mitosis of the T1-prospermatogonia on day 4 and 5 p.p. The nuclei of this cell type are smaller than those of T1-prospermatogonia. T2-prospermatogonia enter mitosis on day 6 p.p and give rise to A-spermatogonia.
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    Development of serotonin-containing cells and the sympathetic innervation of the habenular region in the rat brain (1974)
    Springer
    Cell & tissue research 155 (1974), S. 231-243 
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    ISSN: 1432-0878
    Keywords: Pinealocyte-resembling cells ; Habenular region ; Sympathetic nerve fibres ; Ontogenetic development ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The cells of the pineal gland, the pineal stalk, and the lamina intercalaris contain 5-HT and are innervated by sympathetic nerve fibres. These peripheral nerve fibres continue rostrally from the lamina intercalaris and run into the central nervous tissue of stria medullaris and the habenular nuclei. Pharmacological treatment to increase the cellular 5-HT content revealed that the sympathetic fibres are in close relation to yellow fluorescent cells embedded in the brain tissue. These yellow fluorescent cells develop very late in the ontogenetic development (three weeks or more postnatally) and are preceded by ingrowth of sympathetic fibres into the brain tissue. The results support the hypothesis that the cells found in the habenular region are of pinealocyte rather than neuronal nature, but it is possible that they differ in certain aspects from the cells of the pineal gland proper.
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    Ultrastructure du lobe postérieur de l'hypophyse du rat et ses modifications au cours de l'excrétion de vasopressine (1970)
    Springer
    Cell & tissue research 108 (1970), S. 357-379 
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    ISSN: 1432-0878
    Keywords: Neurohypophysis ; Rat ; Vasopressin release ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé Le lobe postérieur de l'hypophyse a été examiné sur coupes ultrafines chez 45 rats (24 normaux, 17 déshydratés respectivement 1, 2 et 4 jours, et 4 anesthésiés à l'éther), après fixation au glutaraldéhyde ou selon la méthode de Karnovsky, post-fixation osmiée et double contraste à l'acétate d'uranyle et au citrate de plomb. Des fibres neurosécrétoires sombres et claires sont reconnaissables, mais les données manquent encore pour interpréter cette différence. Des densifications juxta-membranaires sont observées dans les terminaisons neurosécrétoires là où se trouvent des amas de microvésicules. Des fibres neurosécrétoires traversent parfois des pituicytes; il est aussi souvent observé des fibres, chargées de granules, libres dans un espace péricapillaire. Les espaces péricapillaires, ramifiés en tous sens loin des vaisseaux, développent une large surface de contact avec les extrémités nerveuses et les prolongements de pituicytes. Dans des conditions techniques bien contrôlées, la déshydratation n'entraîne pas de modifications appréciables des granules de neurosécrétat après 24 h. Ensuite les granules sont diminués en nombre, de façon très considérable le 4e jour; mais les granules restants ont un contenu dense normal; jamais il n'a été observé d'aspects de ≪granules vides ≫. Après anesthésie prolongée à l'éther, il n'y a aucune modification visible ni du nombre, ni de la densité des granules. Ces observations sont discutées quant au mécanisme de l'excrétion de vasopressine; elles sont en faveur de l'existence de deux pools hormonaux, l'un libre et rapidement disponible, l'autre plus fortement lié et certainement contenu dans les granules jouant le rôle de réserve. Toutefois un mécanisme d'exocytose granulaire ne peut être formellement exclu.
    Notes: Summary Hypophysial neural lobes of 45 rats (24 controls, 17 dehydrated resp. 1, 2 and 4 days, and 4 ether anesthetized) were fixed either with glutaraldehyde or according to Karnovsky and post-fixed in osmium tetroxyde; ultrathin sections were stained by uranyl acetate and lead citrate. Dark and clear neurosecretory fibres were observed, but sufficient data are still lacking for a valuable interpretation of these aspects. Juxta-membraneous densifications are visible in limited areas of neurosecretory terminals where clusters of microvesicles are present. Neurosecretory fibres happen to be completely encircled by pituioyte cytoplasm; fibres loaded with elementary granules are frequently encountered running free in a pericapillary space. Pericapillary spaces stretch out branching far away from vessels, resulting in a widespread contact with nerve terminals and pituicyte processes. In accurately controlled technical conditions, dehydratation does not result in any noticeable change of neurosecretory granules after 24 h. A decrease of the number of granules follows and is extremely conspicuous after 4 days; though, remaining granules keep a normal dense content, and aspects of “empty granules” have never been observed. After prolonged ether anesthesia, no visible change either in number or electron density of granules was observed. These findings are discussed in consideration of the mechanism of vasopressin release; they support the hypothesis of two hormonal pools, one of which would be free and rapidly available for release, the other being more tightly bound and certainly located in granules representing a storage site. Though granular exocytosis cannot be absolutely excluded.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00336525
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