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  • Drosophila  (36)
  • hypertension
  • Springer  (47)
  • Cambridge University Press
  • 1980-1984
  • 1975-1979  (47)
  • 1979  (47)
Collection
Keywords
Publisher
  • Springer  (47)
  • Cambridge University Press
Years
  • 1980-1984
  • 1975-1979  (47)
Year
  • 1
    Electronic Resource
    Electronic Resource
    Intercellular junctions during development and in tissue cultures ofDrosophila melanogaster: An electron-microscopic study (1979)
    Springer
    Development genes and evolution 186 (1979), S. 333-349 
    Details
    ISSN: 1432-041X
    Keywords: Imaginal disks ; Intercellular junctions ; Determination ; Pattern formation ; Drosophila
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The present investigation analyzes intercellular junctions in tissues with different developmental capacities. The distribution of junctions was studied inDrosophila embryos, in imaginal disks, and in cultures of disk cells that were no longer able to differentiate any specific pattern of the adult epidermis. The first junctions —primitive desmosomes andclose membrane appositions — already appear in blastoderm.Gap junctions are first detected in early gastrulae and later become more and more frequent.Zonulae adhaerentes are formed around 6 h after fertilization, whileseptate junctions appear in the ectoderm of 10-h-old embryos. Inwing disks of all stages studied (22–120 h), three types of junctions are found: zonulae adhaereentes, gap junctions, and septate junctions. Gap junctions, which are rare and small at 22 h, increase in number and size during larval development. The other types of junctions are found between all cells of a wing disk throughout development. All types of junctions that are found in normal wing disks are also present in theimaginal disk tissues cultured in vivo for some 15 years and in thevesicles of imaginal disk cells grown in embryonic primary cultures in vitro. However, gap junctions are smaller and in the vesicles less frequent than in wing disks of mature larvae. Thus gap junctions, which allow small molecules to pass between the cells they connect, are present in the early embryo, when the first developmental decisions take place, and in all imaginal disk tissues studied, irrespective of whether or not these are capable of forming normal patterns.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00848457
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  • 2
    Electronic Resource
    Electronic Resource
    A high-resolution morphogenetic map of the second-leg basitarsus inDrosophila melanogaster (1979)
    Springer
    Development genes and evolution 187 (1979), S. 129-150 
    Details
    ISSN: 1432-041X
    Keywords: Drosophila ; Pattern formation ; Leg ; Bristle ; Cell lineage
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The lineages of cells on the second-leg basitarsus ofDrosophila melanogaster were analyzed by examining gynandromorphs andMinute mosaics. Bracts lie proximal to bristles on the adult basitarsus, yet bract precursor cells were found to originate lateral to bristle precursor cells. In 6 of the 8 longitudinal rows of bristles on this segment, the bract cells arise ventral to the bristle cells; in the others they arise dorsally. The lateral cell origins are interpreted as reflecting a pattern of lateral cell movements associated with evagination of the leg disc. An unusual discrepancy was observed in the relative frequencies of male vs. female bracts and bristles in gynandromorphs. The discrepancy suggests that there is a cell-autonomous sexual difference in either the time at which cells begin moving during evagination or the speed with which they move. On the basis of the results, it is reasoned that the bristle pattern of the basitarsus does not originate in its final form. Prior to evagination, the bristle cells of each row are apparently closer together than in the final pattern, and the rows are farther apart. Evidence is presented which suggests that the bristle cells of each row may originally be arranged in a jagged line which is later straightened by cell movements. The two locations where the anterior/posterior compartment boundary of the second leg passes through the basitarsus were found to vary relative to the bristle pattern. If this boundary is assumed to be a fixed line of positional values, then the extent of the observed variability — which is estimated to be ± 1 or 2 cell diameters — provides a measure of the precision of patterning around the circumference.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00848267
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  • 3
    Electronic Resource
    Electronic Resource
    Differentiation capacities of the labial imaginal disc ofDrosophila melanogaster (1979)
    Springer
    Development genes and evolution 186 (1979), S. 51-64 
    Details
    ISSN: 1432-041X
    Keywords: Imaginal discs ; Labial disc ; Fate map ; Drosophila ; Homoeosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The mature labial disc, when implanted into a larva of the same age, undergoes metamorphosis along with the host and produces one lateral half of the medi- and distiproboscis. On the basis of results obtained from transplanted disc halves (including the separate peripodial membrane) a tentative fate map of the labial disc was constructed, which shows most of the presumptive mediproboscis to be located in the dorsal, and most of the presumptive distiproboscis in the ventral part of the disc. The distal protion of the peripodial membrane also contains imaginal anlagen, viz. part of the mediproboscis, prementum, and labellar cap anlagen. The involvement of this part of the peripodial membrane was checked by a careful histological analysis of labial disc development during the first ten hours after prepupation. The results were compared with the situation described forCalliphora imaginal discs. In addition, a detailed morphological analysis was made of the proboscis of the homoeotic mutantproboscipedia (pb). At 27°C,pb changes the distiproboscis into a “telopodite” (leg segments distal to the coxa); the (unchanged) prementum may therefore correspond to the coxa. At 15° C, the tarsus of this homoeotic “telopodite” is replaced to a greater or lesser extent by an arista. The present analysis thus confirms (a) the fundamental morphological correspondence of the medi- and distiproboscis with the labium of other insects, and (b) the fundamental developmental correspondence of the labial, antennal, and leg discs.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00848107
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  • 4
    Electronic Resource
    Electronic Resource
    Temperature sensitivity ofTumorous head, a homoeotic mutant ofDrosophila melanogaster (1979)
    Springer
    Development genes and evolution 186 (1979), S. 87-90 
    Details
    ISSN: 1432-041X
    Keywords: Drosophila ; Homoeotic mutant ; Determination
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary A temperature-sensitive period during early embryogenesis for three stocks carrying thetuh-3 gene suggests that it is a homoeotic mutation involved in the initial determination of the eye-antennal disc rather in maintenance of the determination.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00848112
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  • 5
    Electronic Resource
    Electronic Resource
    Regulation and metamorphosis of the abdominal histoblasts ofDrosophila melanogaster (1979)
    Springer
    Development genes and evolution 186 (1979), S. 235-265 
    Details
    ISSN: 1432-041X
    Keywords: Regulation ; Histoblasts ; Drosophila ; Microcautery
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The development of the adult abdomen ofDrosophila melanogaster was analyzed by histology, microcautery, and genetic strategies. Eight nests of diploid histoblasts were identified in the newly hatched larva among the polytene epidermal cells of each abdominal segment: pairs of anterior dorsal, posterior dorsal, and ventral histoblast nests and a pair of spiracular anlagen. The histoblasts do not divide during larval life but begin dividing rapidly 3 h after pupariation, doubling every 3.6 h. Initially they remain confined to their original area, but 15 h after pupariation the nests enlarge, and histoblasts replace adjacent epidermis cell by cell. The histoblasts cover half the abdomen by 28 h after pupariation and the rest by 36 h. Polytene epidermal cells of the intersegmental margin are replaced last. Cautery of the anterior dorsal nest caused deletion of the whole corresponding hemitergite, whereas cautery of the posterior dorsal nest caused the deletion of the macrochaetae of the posterior of the hemitergite. Cautery of the ventral nest deleted the hemisternite and the pleura, whereas cautery of the spiracular anlagen deleted the spiracle. Results of cautery also revealed that no macrochaetae formed on the tergite in the absence of adjacent microchaetae. Clonal analysis revealed that there were no clonal restrictions within a hemitergite at pupariation. Cautery of polytene epidermal cells other than those of the intersegmental margin failed to affect tergite development. However, cautery of polytene epidermal cells of the intersegmental margin adjacent to either dorsal histoblast nest caused mirror-image duplications of the anterior or posterior of the hemitergite in 10% of the hemitergites. Forty percent of the damaged presumptive hemitergites formed complete hemitergites, indicating extensive pattern regulation and regeneration. Pattern duplication and regeneration were accounted for in terms of intercalation and a model of epimorphic pattern regulation (French et al., 1976). Histoblasts in adjacent segments normally develop independently, but if they are enabled to interact by deleting the polytene epidermal cells of the intersegmental margin, they undergo intercalation which results in duplication or regeneration. The possible role of the intersegmental margin cells of insects in development was analyzed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00848591
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  • 6
    Electronic Resource
    Electronic Resource
    cell clones and pattern formation: Studies onsevenless, a mutant ofDrosophila melanogaster (1979)
    Springer
    Development genes and evolution 186 (1979), S. 27-50 
    Details
    ISSN: 1432-041X
    Keywords: Compound eye ; Development ; Determination of R7 cells ; sevenless mutant analysis ; Drosophila
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary sev LY3,the only existing allele at thesev locus (1–33,2±0,2), behaves as strongly hypomorph or even as amorph. Ommatidia in asev compound eye have only seven receptor cells, the position of the R7 pattern element being vacant. Various criteria showing that the missing cell is R7 have been verified. These include (i) anatomical characteristics ofsev ommatidia; (ii) behaviour of central R cells insev rdgB double mutants; (iii) medullary projection of central R cell axons; and (iv) mitotic pattern ofsev imaginal discs. The analysis of morphogeneticsev-sev + mosaics has shown thatsev is expressed autonomously by R7 cells, indicating that thesev phenotype is not due to asev genotype of ommatidial pattern elements other than R7. The study of third instarsev imaginal discs has not brought any direct evidence for death of clustered presumptive R7 cells; however, clonal analysis of the developingsev compound eye has given evidence of developmental parameters comparable to those ofsev +, therefore favouring the hypothesis that R7 cells die insev mutants. On the other hand,sev + seems to be required for the determination of the R7 cells, since thesev phenotype cannot be uncovered during the last mitoses of heterozygous mutant cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00848106
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  • 7
    Electronic Resource
    Electronic Resource
    Regulative interaction of mature imaginal disc Fragments with embryonic and immature disc tissues inDrosophila (1979)
    Springer
    Development genes and evolution 187 (1979), S. 1-11 
    Details
    ISSN: 1432-041X
    Keywords: Imaginal discs ; Drosophila ; Pattern regulation embryos
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary These experiments examined whether inDrosophila immature imaginal disc tissue and tissues from embryonic stages can influence pattern regulation in a disc fragment in the same way as can mature imaginal discs. Immature imaginal discs, or the cells of whole embryos, were mixed with a test fragment (presumptive notum) from a mature wing disc. The immature tissues in each mixture were genetically marked and had been heavily irradiated (25 Kr gamma) prior to mixing to prevent growth and maturation during subsequent culture in vivo. Alteration of the regulative behavior of the test fragment (that is, regeneration of wing) thus provided an assay for the communication of positional information by the immature tissues. The results suggest that this capacity arises well before competence to metamorphose, as early as the 16th hour of embryonic development, whereas prior to 16 h, essentially no stimulation of regeneration occurred. It is suggested that the imaginal disc (or presumptive disc) cells of the embryo may have been responsible for this early stimulatory capacity.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00848162
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  • 8
    Electronic Resource
    Electronic Resource
    A comparative study of embryonic gene expression inDrosophila andEphestia (1979)
    Springer
    Development genes and evolution 187 (1979), S. 81-88 
    Details
    ISSN: 1432-041X
    Keywords: Drosophila ; Ephestia ; Allozymes ; Gene activation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The ontogeny of allozyme patterns has been studied in embryos ofDrosophilamelanogaster, which are doubly heterozygous for alleles specifying the slow and fast forms of alcohol dehydrogenase (ADH) and α-glycerophosphate dehydrogenase (GPDH). The ontogeny of esterase-2 was studied in embryos and young larvae of the flour mothEphestia kühniella, which are heterozygous for two of the three existing esterase-2 alleles. In freshly laidDrosophila eggs only the maternal enzyme forms are present and during the first 15 hours of development the staining of these forms becomes progressively fainter. After 16 and 17 h, the paternal and hybrid bands of ADH and GPDH respectively become obvious. Before hatching, the intensity distribution in the three-banded pattern of reciprocal hybrids is asymmetric in favour of the persisting maternal enzyme form. InEphestia embryos, however, there is no persistence of the maternal esterases. In all reciprocal heterozygotes a three-banded pattern suddenly appears 96 h after egg deposition, indicating synchronous activation of both parental alleles. The relative intensity distribution in the hybrid patterns approaches that of the mature larvae stepwise and in an allele-specific manner. This result and the fact that the various heterozygous types exhibit unequal total activities suggest that the Esterase-2 alleles have different activities, which are fixed late in embryogenesis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00848169
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  • 9
    Electronic Resource
    Electronic Resource
    In vitro development of theDrosophila chorion in a chemically defined organ culture medium (1979)
    Springer
    Development genes and evolution 186 (1979), S. 351-362 
    Details
    ISSN: 1432-041X
    Keywords: Eggshell ; Chorion ; In vitro development ; Drosophila ; Tissue culture media
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary TheDrosophila chorion is produced normally in isolated follicles in Robb's chemically defined culture medium. The complex architecture of the shell developed in vitro from follicles as young as early stage 10 is completely normal morphologically. In addition, the time required for in vitro development closely approximates that observed for in vivo development. Comparisons of insect culture media developed by Robb, Grace, Schneider, and Echalier show large variations in their ability to supportDrosophila chorion development.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00848458
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  • 10
    Electronic Resource
    Electronic Resource
    Pattern as a function of cell number and cell size on the second-leg basitarsus ofDrosophila (1979)
    Springer
    Development genes and evolution 187 (1979), S. 105-127 
    Details
    ISSN: 1432-041X
    Keywords: Drosophila ; Pattern formation ; Leg ; Bristle ; Evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The bristle pattern of the second-leg basitarsus inDrosophila melanogaster was studied as a function of the number and size of the cells on this segment in well-fed and starved wild-type flies, in triploid flies, and in two mutants (dachs andfour-jointed) that have abnormally short basitarsi. The second-leg basitarsi of well-fed, wild-type flies from 22 otherDrosophila species were studied in a similar manner. There are typically 8 longitudinal rows of evenly-spaced bristles on the second-leg basitarsus, and in each row the number of bristles was consistently found to vary in proportion to the estimated number of cells along the segment, and the interval between bristles was found to vary in proportion to the average cell diameter on the segment. These correlations are interpreted to mean that the spacing of the bristles within each row is controlled developmentally, whereas the number of bristles is not. The interval between bristles is evidently measured either as a fixed number of cells or as a distance which indirectly depends upon cell diameter.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00848266
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  • 11
    Electronic Resource
    Electronic Resource
    A comparative ultrastructural study of ‘glue’ production and secretion of the salivary glands in different species of theDrosophila melanogaster group (1979)
    Springer
    Development genes and evolution 187 (1979), S. 329-354 
    Details
    ISSN: 1432-041X
    Keywords: Glue proteins ; Secretory proteins ; Drosophila
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Salivary gland cells of members of theDrosophila melanogaster group (from four different subgroups) were examined electron microscopically and histochemically during the late larval period of development. The secretory product, which is supposed to be utilized as ‘glue’ at the time of puparium formation, appears, by analogy to Palade and Jamieson's results, to be synthesized partially in the rough endoplasmic reticulum (RER) and partially in the Golgi complex. The latter is also the usual site of the packaging of the product into secretory granules, except in the case of one of the secretory granule components ofD. lucipennis. The phylogenetic relationships among the subgroups, implied by the morphological appearance of the secretory granules, fit well with the existing phylogenetic relationships within the group. The secretory granules of each species have their own morphological features; granules of species of the same subgroup share some of these features. Secretion occurs from the cells via exocytosis during which the morphology of the secretory granules changes. Light microscope examination of PAS (Periodic Acid-Schiff reaction) stained glands shows a strong positive reaction in most species, with the exception of the species of thesuzukii subgroup which show a weak, or a negative reaction (D. rajasekari). Electron histochemical localization of polysaccharides in the secretory granules was possible inD. melanogaster and the species of theananassae subgroup.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00848468
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  • 12
    Electronic Resource
    Electronic Resource
    Autonomous yolk protein synthesis in ovaries ofDrosophila cultured in vivo (1979)
    Springer
    Development genes and evolution 187 (1979), S. 255-266 
    Details
    ISSN: 1432-041X
    Keywords: Yolk proteins ; Hormonal control ; Electrophoresis ; In vivo culture ; Drosophila
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Immature ovaries ofDrosophila mercatorum were injected into young larvae and into adult males ofD. mercatorum, D. melanogaster, D. hydei, D. virilis, andZaprionius vittiger. These homo- and heteroplastic transplantations allow normal vitellogenesis to occur in the donor ovary. By SDS gel electrophoresis, we identified the major species-specific yolk proteins of mature eggs (stage 14) which were exclusively of donor-specific origin. Other experiments withD. hydei andZ. vittiger showed that, when females were used as hosts, the host-specific yolk proteins became incorporated into the donor eggs. When two immature ovaries, one ofD. mercatorum and one ofD. hydei, were co-cultured in males, again only the donor-specific yolk proteins were found in the mature eggs implying that these yolk proteins were not released into the host hemolymph. A parthenogenetic strain ofD. mercatorum was used to demonstrate the ability of transplanted immature ovaries to produce viable eggs which can give rise to fertile adults. The role of the species-specific yolk proteins is discussed with respect to the dual origin of these proteins during normal vitellogenesis, i.e., an autonomous synthesis within the ovary itself in addition to the well-known production by the fat body. Further experiments with pupae as hosts indicate that even in the absence of juvenile hormone and in the presence of high doses of ecdysone, vitellogenesis can proceed within the donor ovary. Based on these experiments, a new hyopthesis on the hormonal control of vitellogenesis inDrosophila is presented. We propose that yolk proteins derived from the fat body are controlled by juvenile hormone, whereas the independent and autonomous vitellogenesis within the ovary itself is controlled by endogenously synthesized ecdysone.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00848621
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  • 13
    Electronic Resource
    Electronic Resource
    Early development of the thoracic discs ofDrosophila (1979)
    Springer
    Development genes and evolution 187 (1979), S. 375-379 
    Details
    ISSN: 1432-041X
    Keywords: Drosophila ; Segmentation ; Primordial size ; Gynandromorphs ; Bithorax mutants
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary We estimate the number of blastoderm cells which generate the thoracic imaginal discs ofDrosophila. At hatching the wing disc is twice the size of the haltere disc, but the results suggest that both discs develop from a similar number of blastoderm cells. Two homeotic mutations, which transform the haltere into wing, affect embryonic growth but not the primordial number. All the segmental primordia may be of similar size and each may be similarly subdivided into a larger anterior, and a smaller posterior polyclone.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00848471
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  • 14
    Electronic Resource
    Electronic Resource
    Fusion ofDrosophila eye-antennal imaginal discs during differentiation in vitro (1979)
    Springer
    Development genes and evolution 185 (1979), S. 363-370 
    Details
    ISSN: 1432-041X
    Keywords: Drosophila ; Imaginal discs ; Pattern formation ; β-ecdysone ; Tissue culture
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Pairs of eye-antennal discs, attached to the cephalic ganglia, were cultured in vitro with a concentration of β-ecdysone optimal for imaginal differentiation. The eye-antennal discs fused to form a vesicle inside which the antennae were partially everted, and on the inner surface of which imaginal structures differentiated. The epithelium of the discs was continuous, and an integrated pattern of bristles and hairs differentiated in vitro. In particular, the median ocellus, a unified structure derived partially from each disc, differentiated normally.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00848522
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  • 15
    Electronic Resource
    Electronic Resource
    Pattern specification in imaginal discs ofDrosophila melanogaster (1979)
    Springer
    Development genes and evolution 186 (1979), S. 1-25 
    Details
    ISSN: 1432-041X
    Keywords: Drosophila ; Leg imaginal disc ; Pattern duplication ; Genetic mosaics ; Compartments
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary l(1)su(f)mad-ts (mad) is a new temperature-sensitive (ts) lethal mutant ofDrosophila melanogaster which produces duplicated legs after temperature pulse treatment during larval development. The ts-lethality was studied in temperature experiments and genetic mosaics. Temperature pulses given during two distinct TSPs of larval development result in two different types of leg pattern duplication. “Total” differ from “partial” duplications with respect to the affected leg compartments and the orientation of the planes of symmetry which are perpendicular to the dorso-ventral and the proximo-distal leg axes in total and partial duplications, respectively. Genetic mosaic studies indicate (i) disc autonomy of leg pattern duplication, (ii) clonal separation of the anlagen of the two pattern copies, and (iii) clonal restriction along the antero-posterior compartment border in the two pattern copies of totally duplicated legs. The results suggest thatmad leg pattern duplication is caused by a change in positional information rather than by cell death and subsequent regeneration. Our data are compatible with the assumption that during normal development the leg disc cells acquire information about their position within the disc with respect to the different leg axes independently and at different times.
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    URL: http://dx.doi.org/10.1007/BF00848105
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  • 16
    Electronic Resource
    Electronic Resource
    A clonal analysis of the relationship of duplicated bristles inDrosophila (1979)
    Springer
    Development genes and evolution 186 (1979), S. 267-271 
    Details
    ISSN: 1432-041X
    Keywords: Drosophila ; Bristle formation ; Differential divisions ; Clonal analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Two possible mechanisms are considered for the occurrence of experimentally or genetically induced duplications of bristles: extra cell division of a bristle mother cell versus determination of more than one mother cell. From a clonal analysis it appears that duplications induced by actinomycin-D arise by the latter mechanism, whereas those found in the mutantspl seem to arise by the former mechanism.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00848592
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  • 17
    Electronic Resource
    Electronic Resource
    Influence of metoprolol, alone and in combination with a thiazide diuretic, on blood pressure, plasma volume, extracellular volume and glomerular filtration rate in essential hypertension (1979)
    Springer
    European journal of clinical pharmacology 15 (1979), S. 305-310 
    Details
    ISSN: 1432-1041
    Keywords: metoprolol ; thiazides diuretics ; hypertension ; haemodynamic effects ; renal function ; body fluid volume
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary In fifteen patients with essential hypertension WHO I–II (eight men and seven; mean age 45 years) blood pressure (BP), plasma volume (PV;125I-Albumin space), extracellular volume (ECV;82Brdistribution space) and glomerular filtration rate (GFR;51Cr-EDTA clearance) were measured before and during long-term antihypertensive therapy with metoprolol, alone, and in combination with thiazide diuretics. Metoprolol given alone to all patients for an average of 5 months (mean dose 230 mg) resulted in a reduction in systolic and diastolic pressure by 11% and 8%, respectively. In eight patients the BP reduction was considered inadequate (non-responders). In the group as a whole, ECV increased significantly by 5%. The increase in ECV in the non-responders was five times larger than in the responders (1.025 ml against 205 ml), which may in part account for the inadequate BP control. Addition of a thiazide diuretic for an average of 3.5 months resulted in reduction of ECV to its pretreatment level and a pronounced additional fall in BP, comparable to that in the responders. No systematic change in PV or GFR could be demonstrated. No difference was found between the two groups regarding sex, pretreatment BP, body fluid volumes or renal function. On average the non-responders were 20 years older than the responders. The clinical importance of the apparent age-related expansion of ECV and the mechanism behind fluid retention during antihypertensive treatment with beta-blocking drugs are discussed. As failure of BP control during treatment with beta-blockers may be due to fluid retention, concurrent use of diuretics is indicated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00558432
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  • 18
    Electronic Resource
    Electronic Resource
    Effect of oral labetalol on plasma catecholamines, renin and aldosterone in patients with severe arterial hypertension (1979)
    Springer
    European journal of clinical pharmacology 16 (1979), S. 305-310 
    Details
    ISSN: 1432-1041
    Keywords: labetalol ; furosemide ; hypertension ; aldosterone ; blood pressure ; plasma catecholamines ; renin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary Arterial blood pressure and plasma catecholamines, renin activity and aldosterone concentration in 12 patients with severe essential hypertension were studied before and after combined α-and β-adrenergic receptor blockade induced by oral labetalol treatment for 2 months. Furosemide in a fixed dose was employed as a basic antihypertensive agent throughout the study. Blood pressure was adequately controlled in only 6 patients. Mean body weight increased by 1.8 kg and there was a rise in body weight which was inversely correlated with the fall in standing mean blood pressure. The mean plasma noradrenaline concentration decreased from 0.30 to 0.20 ng/ml, whereas plasma adrenaline did not change significantly. Plasma renin activity and aldosterone concentration varied greatly, but the mean values did not change significantly. Change in body weight was correlated inversely with changes in plasma noradrenaline and renin. The results suggest that labetalol, through its combined α- and β-adrenergic receptor blocking action, induces a rise in body weight, probably due to sodium and fluid retention, which partly counterbalances the antihypertensive effect of labetalol, and partly modifies both renin and sympathetic nervous activity.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00605626
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  • 19
    Electronic Resource
    Electronic Resource
    Multicentre comparative trial of tienilic acid and hydrochlorothiazide in hypertensive patients (1979)
    Springer
    European journal of clinical pharmacology 16 (1979), S. 319-322 
    Details
    ISSN: 1432-1041
    Keywords: tientilic acid ; hydrochlorothiazide ; hypertension ; diuretics ; hyperuricemia ; hypouricemic drugs
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary To compare the clinical and metabolic effects of a new diuretic uricosuric agent, tienilic acid, with those of hydrochlorothiazide, a multicentre double-blind trial was performed in 56 hypertensive patients. Twenty — eight patients were randomly assigned to take tienilic acid and 28 to take hydrochlorothiazide. The diuretic and anti-hypertensive actions of the two compounds were similar. No significant differences were observed between tienilic acid and hydrochlorothiazide in their effects on urinary and serum electrolytes, hepatic and renal function tests, and fasting lipids. The patients who received tienilic acid showed a significant fall in serum uric acid, mediated by the uricosuric effect. The availability of an agent combining diuretic, anti-hypertensive and hypouricemic effects offers promise in the treatment of arterial hypertension.
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    Dissociation of biochemical and hypotensive effects of debrisoquine in hypertensive patients (1979)
    Springer
    European journal of clinical pharmacology 16 (1979), S. 81-86 
    Details
    ISSN: 1432-1041
    Keywords: debrisoquine ; hypertension ; renin ; catecholamines ; platelet monoamine oxidase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary The 24 h urinary excretion of adrenaline, noradrenaline, metadrenaline, normetadrenaline and vanillylmandelic acid, plasma renin activity and plasma and urinary debrisoquine were measured before and during chronic treatment with oral debrisoquine in 14 in-patients with essential hypertension. There was a significant fall (mean ±SD) in the 24 h urinary excretion of vanillylmandelic acid (15.3±2.8 to 6.7±1.9 µmol) noradrenaline (199.0±105.8 to 125.2±43.3 nmol) and plasma renin activity (0.71±0.47 to 0.40±0.20 pmol Angio I ml−1 h−1) while the urinary normetadrenaline/noradrenaline ratio increased (10.4±6.1 to 17.1±5.1). No significant change was seen in the output of adrenaline or of O-methylated metabolites. Debrisoquine produces extensive noncompetitive inhibition of platelet monoamine oxidase in vivo at low therapeutic plasma concentrations. These changes support the view that treatment with debrisoquine produces intraneuronal inhibition of monoamine oxidase and post-ganglionic blockage. There was a significant correlation between the change in standing diastolic blood pressure and the daily dose (rs=−0.52), pre-dose plasma concentration (rs=−0.85) and mean daily urinary recovery (rs=−0.80), of debrisoquine. The full extent of the biochemical changes were seen at low dose and low plasma concentration and were not directly correlated with the fall in standing or supine blood pressure.
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    Long-term hemodynamic effects of penbutolol at rest and during exercise in essential hypertension (1979)
    Springer
    European journal of clinical pharmacology 16 (1979), S. 149-153 
    Details
    ISSN: 1432-1041
    Keywords: beta-adrenergic blockade ; penbutolol ; haemodynamics ; hypertension ; prolonged treatment
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary Thirteen men with previously untreated essential hypertension (WHO Stage I) were studied as out-patients. Oxygen consumption, heart rate, cardiac index and brachial arterial pressure were recorded at rest supine and whilst sitting position, and during steady state exercise at 50, 100 and 150 W. The subjects were then treated with penbutolol 20–80 mg/day. In 12 responding patients hemodynamic study after 1 year demonstrated that systolic, diastolic and mean arterial pressure were reduced by approximately 20% at rest and 18% during exercise. Heart rate was reduced about 24% at rest and 26% during exercise. The stroke index did not show any significant change during rest, but during exercise the post-treatment values were 8%, 13% and 18% higher than the pre-treatment values at the 50, 100 and 150 W exercise levels, the last two changes being significant. Thus, the reduction in cardiac index during exercise was less than the reduction in heart rate — about 15%, but 24% when sitting at rest. The total peripheral resistance index did not show any significant change at rest or during exercise. Dizziness or muscular fatigue occurred in 6 patients during the first two weeks of treatment. From then on no side-effects were noted. It is concluded that the hemodynamic effects of longterm treatment with penbutolol in mild to moderate hypertension largely resemble those after the majority of other beta-blockers.
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    Double-blind comparison of metoprolol, alprenolol, and oxprenolol in hypertension (1979)
    Springer
    European journal of clinical pharmacology 16 (1979), S. 369-374 
    Details
    ISSN: 1432-1041
    Keywords: metoprolol ; alprenolol ; oxprenolol ; hypertension ; double-blind trial
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary A double-blind comparison of the β-blockers metoprolol, alprenolol and oxprenolol was carried out to evaluate their antihypertensive effect and tolerability. 105 patients with previously untreated hypertension entered the trial and 71 completed it. Side-effects were infrequent and were never the reason for drop-out. All three drugs caused a statistically significant reduction in blood-pressure at the lower of the two doses used during a dose-finding period. At the higher dose employed in this period, metoprolol caused a significantly greater reduction in diastolic blood-pressure than did alprenolol or oxprenolol. All three drugs caused a significant reduction in heart rate. During the follow-up period, the β-blockers were supplemented if necessary with hydrochlorothiazide. This was required less frequently in the metoprolol group than in the other two groups.
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    Hypotensive action and side-effects of flutonidin in normal subjects (1979)
    Springer
    European journal of clinical pharmacology 16 (1979), S. 375-379 
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    ISSN: 1432-1041
    Keywords: flutonidin ; clonidine ; hypertension ; side effects
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary In a double blind study, planned as a 7×7 latin square, three oral doses of futonidin (0.5, 1, 2 mg), of clonidine (0.0075, 0.150, 0.300 mg) and of a placebo were administered to 7 normal volunteers on 7 different treatment days, with an interval of 3 days. On each treatment day sitting blood pressure, heart rate and reaction time were measured, and sedation and dry mouth evaluated before and 1, 2, 3, 4, 6, and 8 h after administration. The placebo did not modify the basal value of any variable. Flutonidin and clonidine produced dose-related effects on blood pressure, heart rate, sedation and dry mouth, but did not influence reaction time. Analysis of the dose-response curves demonstrated that the effect of flutonidin was one-fifth to one-twelfth that of clonidine, depending on which variable was considered.
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    Comparison of once and twice daily administration of sotalol in the treatment of hypertension (1979)
    Springer
    European journal of clinical pharmacology 15 (1979), S. 293-298 
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    ISSN: 1432-1041
    Keywords: sotalol ; hypertension ; once and twice daily dose ; three daily BP-readings ; plasma concentration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary Thirty patients with mild to severe essential hypertension, satisfactorily controlled by twice daily Sotalol 80 to 320 mg/day, entered a double-blind, crossover study comparing the efficacy, tolerability and safety of their usual twice daily dose of Sotalol with the same total dose given once daily. Each double-blind period was eight weeks long; during it blood pressure and pulse rate were measured in each patient's home at 8–10 a. m., 12-2 p. m. and 8–10 p. m., on alternate days during the last week of each treatment period. There was no significant difference in blood pressure or pulse rate between each regime for the three readings during the day. The mean serum concentration of Sotalol twenty-four hours after once daily administration was not significantly lower than the concentration 12 h after twice daily administration. Once daily dosage did not cause any problems of tolerance.
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    Purification and properties of the enzymes from Drosophila melanogaster that catalyze the synthesis of sepiapterin from Dihydroneopterin triphosphate (1979)
    Springer
    Biochemical genetics 17 (1979), S. 371-390 
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    ISSN: 1573-4927
    Keywords: sepiapterin ; Drosophila ; biosynthesis ; pteridines
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Sepiapterin synthase, the enzyme system responsible for the synthesis of sepiapterin from dihydroneopterin triphosphate, has been partially purified from extracts of the heads of young adult fruit flies (Drosophila melanogaster). The sepiapterin synthase system consists of two components, termed “enzyme A” (MW 82,000) and “enzyme B” (MW 36,000). Some of the properties of the enzyme system are as follows: NADPH and a divalent cation, supplied most effectively as MgCl2, are required for activity; optimal activity occurs at pH 7.4 and 30 C; the K m for dihydroneopterin triphosphate is 10 µm; and a number of unconjugated pterins, including biopterin and sepiapterin, are inhibitory. Dihydroneopterin cannot be used as substrate in place of dihydroneopterin triphosphate. Evidence is presented in support of a proposed reaction mechanism for the enzymatic conversion of dihydroneopterin triphosphate to sepiapterin in which enzyme A catalyzes the production of a labile intermediate by nonhydrolytic elimination of the phosphates of dihydroneopterin triphosphate, and enzyme B catalyzes the conversion of this intermediate, in the presence of NADPH, to sepiapterin. An analysis of the activity of sepiapterin synthase during development in Drosophila revealed the presence of a small amount of activity in eggs and young larvae and a much larger amount in late pupae and young adults. Sepiapterin synthase activity during development corresponds with the appearance of sepiapterin in the flies. Of a variety of eye color mutants of Drosophila melanogaster tested for sepiapterin synthase activity, only purple (pr) flies contained activity that was significantly lower than that found in the wild-type flies (22% of the wild-type activity). Further studies indicated that the amount of enzyme A activity is low in purple flies, whereas the amount of enzyme B activity is equal to that present in wild-type flies.
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    Genetic and cytogenetic studies of four glycolytic enzymes in Drosophila melanogaster: Aldolase, triosephosphate isomerase, 3-phosphoglycerate kinase, and phosphoglucomutase (1979)
    Springer
    Biochemical genetics 17 (1979), S. 769-783 
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    ISSN: 1573-4927
    Keywords: Drosophila ; aldolase ; triosephosphate isomerase ; glycolysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Four glycolytic enzymes in Drosophila melanogaster have been genetically and/or cytogenetically mapped. The structural gene for aldolase (Ald) has been genetically mapped to 3-91.5 and cytogenetically localized to 97A-B. Tpi, the structural gene for triosephosphate isomerase, has been genetically mapped to 3-101.3 and cytogenetically localized to 99B-E. Utilizing closer-flanking markers than the previous mapping, Pgk, the structural gene for 3-phosphoglycerate kinase, has been mapped to 2-5.9; cytogenetically it was found to lie in the interval between 22D and 23E3. The cytogenetic location of Pgm, the structural gene for phosphoglucomutase which has been located genetically at 3-43.4, was determined to be in 72D1-5.
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    Ontogeny, cell distribution, and the physiological role of NADP-malic enzyme in Drosophila melanogaster (1979)
    Springer
    Biochemical genetics 17 (1979), S. 867-879 
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    ISSN: 1573-4927
    Keywords: malic enzyme ; development ; NADP enzymes ; Drosophila ; nutrition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract NADP-malic enzyme (NADP-ME) (E.C. 1.1.1.40) is situated in the cytosol of Drosophila melanogaster. Both the tissue activity and CRM level of NADP-ME parallel changes in the dosage of a gene, Men +, located in region 87C2-3 to 87D1-2 of the third chromosome. The tissue activity of NADP-ME is very high in early third instar larvae, providing about 33% of the NADPH at this life stage. The tissue activity declines during pupal development but increases as the adult ages. The concentration of NADP-ME CRM and tissue activity are coordinately increased in third instar larvae by dietary carbohydrate and decreased by dietary lipid.
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    Genetic and biochemical aspects of sucrase from Drosophila melanogaster (1979)
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    Biochemical genetics 17 (1979), S. 897-907 
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    ISSN: 1573-4927
    Keywords: sucrase ; Drosophila ; segmental aneuploidy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Isoelectrofocusing of abdominal extracts of Drosophila melanogaster revealed the existence of two forms of sucrase (E.C. 3.2.1.26). One form exhibited an isoelectric point of 4.63±0.02 while the other form exhibited an isoelectric point of 4.83±0.02. The localization of the structural gene for sucrase is proposed on the basis of enzyme determinations in a series of duplication- and deletion-bearing aneuploids. We suggest that the sucrase structural gene lies between 31CD and 31EF on the left arm of chromosome 2 and that the two forms of abdominal sucrase derive from a common protein coded for by a single sucrase gene designated Sucr +.
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    Genetic and cytogenetic studies of the malate dehydrogenases of Drosophila melanogaster (1979)
    Springer
    Biochemical genetics 17 (1979), S. 947-956 
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    ISSN: 1573-4927
    Keywords: malate dehydrogenase ; cytoplasmic ; mitochondrial ; cytogenetic ; Drosophila
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Genetic and cytogenetic locations of the structural genes for the NAD-dependent malate dehydrogenases have been studied. The mitochondrial form (mMDH) is coded for by a gene (Mdh) found at 62.6 on the third chromosome and included in Df(3R)P14, which includes 90C2–91A3 in the salivary gland chromosomes. Based on its inclusion within several J (Jammed; 2–41.0) deficiencies, the structural gene (cMdh) for the cytoplasmic form (cMDH) was determined to lie in region 31B-E, confirming the earlier finding of Grell. Flies lacking any cMDH activity (cMdhn-γ10069/ Df(2L)J-der-27) were both viable and fertile.
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    Drosophila alcohol dehydrogenase activity in vitro and in vivo: Effects of acetone feeding (1979)
    Springer
    Biochemical genetics 17 (1979), S. 553-563 
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    ISSN: 1573-4927
    Keywords: alcohol dehydrogenase ; Drosophila ; acetone ; multiple forms
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract When adult Drosophila are placed on medium containing 0.5% acetone, their level of alcohol dehydrogenase activity drops rapidly. At the same time, the proportion of activity in the various electrophoretic forms of the enzyme shifts; most of the activity becomes localized in what is ordinarily a minor form of the enzyme. Moreover, the loss of enzyme activity occurs in vivo as well, as shown by sensitivity to ethanol poisoning, insensitivity to pentenol treatment, and inability to utilize ethanol as an energy source. These observations are discussed in light of a model advanced for the origin of the multiple forms of alcohol dehydrogenase in Drosophila.
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    Form II DNA-dependent RNA polymerase from Drosophila melanogaster: General in vitro catalytic properties and template interactions (1979)
    Springer
    Biochemical genetics 17 (1979), S. 77-95 
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    ISSN: 1573-4927
    Keywords: Drosophila ; form II RNA polymerase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Several in vitro properties of partially purified form II RNA polymerase from Drosophila melanogaster embryo nuclei are described. The enzyme preparation is free from contaminating RNase, protein kinase, and polyphosphate kinase activities and can be used to study the incorporation of γ-32P-labeled nucleoside triphosphates. The enzyme exhibits a biphasic heat inactivation pattern which is probably related to differential lability of its two subforms. However, a considerable protection against heat inactivation is provided by the nucleoside triphosphates present in the in vitro reaction system such that the enzyme catalyzes RNA synthesis in a nearly linear mode for over 2 hr at 30 C. Two initiation inhibitors, rifamycin AF/013 and polyriboinosinic acid (poly[I]), were tested against this enzyme. Rifamycin AF/013 was found unsuitable for critical studies because of the high concentrations necessary for total inhibition (200 µg/ml) and particularly because of the obligate use of solvents which secondarily have a destabilizing effect on native DNA. Poly[I] was found to effectively block initiation at very low concentrations (1 µg/ml). The enzyme rapidly forms poly[I]-resistant preinitiation complexes on both double- and single-stranded DNA. These complexes decay with a half-life of 2.5–3 min. RNA synthesis from poly[I]-resistant complexes amounts to 10% of the total potential synthesis on both double- and single-stranded DNA. Enzyme-DNA saturation experiments indicate that the form II enzyme discriminates two types of sites on Drosophila DNA, tight binding and weak binding, from which RNA synthesis proceeds slowly and rapidly, respectively. The tight-binding sites appear to be analogous to those sites with which the enzyme is able to form poly[I]-resistant complexes.
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    Allozyme genotype-environment relationships in natural populations of Drosophila buzzatii (1979)
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    Biochemical genetics 17 (1979), S. 105-126 
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    ISSN: 1573-4927
    Keywords: Drosophila ; electrophoresis ; enzyme polymorphism ; genotype-environment associations ; natural selection
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Allozyme frequency data from natural populations of Drosophila buzzatii were analyzed for genotype-environment relationships. Allele frequency and heterozygosity at six loci polymorphic throughout eastern Australia and a number of environmental factors (both means and variabilities) were examined by a variety of multivariate techniques. Significant genotype-environment associations were found for five of the six loci, and after correcting for geographic location significant associations remained for Est-2 and Adh-1 gene frequencies and heterozygosities and for Pgm gene frequencies. The results are discussed in relation to selection and gene flow and provide the basis for laboratory studies to disentangle confounded effects of (1) environmental means and environmental variabilities and (2) allele frequency and heterozygosity, and thus to further test for and determine the nature of any natural selection at particular allozyme loci.
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    Studies of esterase 6 in Drosophila melanogaster. I. The genetics of a posttranslational modification (1979)
    Springer
    Biochemical genetics 17 (1979), S. 167-183 
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    ISSN: 1573-4927
    Keywords: esterase 6 ; Drosophila ; enzyme modification ; leucine aminopeptidase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract A locus has been found, an allele of which causes a modification of some allozymes of the enzyme esterase 6 in Drosophila melanogaster. There are two alleles of this locus, one of which is dominant to the other and results in increased electrophoretic mobility of affected allozymes. The locus responsible has been mapped to 3-56.7 on the standard genetic map (Est-6 is at 3-36.8). Of 13 other enzyme systems analyzed, only leucine aminopeptidase is affected by the modifier locus. Neuraminidase incubations of homogenates altered the electrophoretic mobility of esterase 6 allozymes, but the mobility differences found are not large enough to conclude that esterase 6 is sialylated.
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    The α-glycerophosphate dehydrogenase (α-gpdh) polymorphism in Drosophila melanogaster: adult survival under temperature stress (1979)
    Springer
    Theoretical and applied genetics 54 (1979), S. 235-237 
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    ISSN: 1432-2242
    Keywords: Drosophila ; α-Glycerophosphate dehydrogenase ; Polymorphism ; Temperature selection
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary As a test of the hypothesis that adult temperature stress is an important component of natural selection maintaining the α-gpdh polymorphism, we have looked for differential survival among genotypes subjected to (i) heat shock and (ii) cold shock. Factorial ANOVAR, taking account of genotype, sex and temperature-stress indicated that genotype did not contribute to the variance of survival proportion per vial. We have not therefore found evidence to support our hypothesis. Incidental to the above was a significant sex-temperature interaction. Thus, adult females showed higher survival than males under heat stress, while under cold stress, there was no indication of a survival difference between the sexes.
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    Increased sensitivity of adipose tissue of spontaneously hypertensive rats to ACTH (1979)
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    Bulletin of experimental biology and medicine 88 (1979), S. 696-699 
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    ISSN: 1573-8221
    Keywords: hypertension ; ACTH ; lipolysis ; calcium
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The action of ACTH on lipolysis was studied in the adipose tissue of rats with spontaneous and renal hypertension and also in normotensive rats of corresponding control groups. The sensitivity of the adipose tissue of SHR rats to ACTH was shown to be higher than in the normotensive control. Evidence was obtained that this increase in sensitivity is due to the state or quantity of intracellular calcium. In rats with renal hypertension no such increase in sensitivity of their adipose tissue to ACTH was found.
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    Effect of the β-adrenoblocker propranolol on adrenalin lipolysis in adipose tissue of rats with spontaneous genetic hypertension (1979)
    Springer
    Bulletin of experimental biology and medicine 88 (1979), S. 1285-1286 
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    ISSN: 1573-8221
    Keywords: hypertension ; adrenalin ; propranolol ; adipose tissue
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The action of the β-adrenoblocker propranolol on adrenalin lipolysis was studied in adipose tissue of rats with spontaneous hypertension and of control rats. The degree of lipolysis was judged from the accumulation of glycerol in the incubation mediumin vitro. The maximal response of adipose tissue to adrenalin was found to be the same in rats with hypertension and control animals. The adrenalin concentration evoking half the maximal response (KA) in rats with hypertension was found to be half that observed in control rats. In the presence of propranolol this parameter increased more in SHR rats than in the controls. The results indicate increased sensitivity of the adipose tissue of SHR rats to propranolol, possibly in connection with changes in the properties of the β-adrenoreceptor in this form of hypertension.
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    Preparation of cell cultures fromDrosophila melanogaster embryos (1979)
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    Methods in cell science 5 (1979), S. 1019-1022 
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    ISSN: 1573-0603
    Keywords: cell cultures ; Drosophila ; cell differentiation ; embryos
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
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    Preparative isolation and short-term organ culture of imaginal discs ofDrosophila melanogaster (1979)
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    Methods in cell science 5 (1979), S. 1055-1062 
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    ISSN: 1573-0603
    Keywords: Drosophila ; imaginal discs ; ecdysteroids ; morphogenesis ; organ culture
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
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    Oviposition site preference inDrosophila (1979)
    Springer
    Behavior genetics 9 (1979), S. 233-241 
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    ISSN: 1573-3297
    Keywords: Drosophila ; oviposition site preference ; ethanol ; Darwininian fitness
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Psychology
    Notes: Abstract Comparative studies of oviposition site preference (OSP) inDrosophila suggest that choice of oviposition site is an important adaptive behavior which influences individual fitness and the potential of populations for speciation. OSP has been investigated under conditions which provided females with a choice of standard medium or medium containing ethanol for oviposition. OSP is an extremely labile behavior in the laboratory, but a technique has been developed which minimizes variation between replicates and allows the detection of OSP differences between semispecies of a single species. An analysis of the OSP of 14Drosophila species shows that this behavior is not correlated with phylogenetic relationships. OSP with respect to ethanol may be correlated with the presence of ethanol in the environment and the activity of alcohol dehydrogenase in the species tested.
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    Inbreeding and heterogamic mating: An alternative to Averhoff and Richardson (1979)
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    Behavior genetics 9 (1979), S. 249-256 
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    ISSN: 1573-3297
    Keywords: mating speed ; sexual vigor ; inbreeding ; Drosophila
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Psychology
    Notes: Abstract An alternative explanation to the pheromonal control of mating through chemoreceptor saturation proposed by Averhoff and Richardson (1974) is offered for the apparent rise in heterogamic mating in their experiments, after several generations of full-sib mating. In a multiple-choice mating between two genotypic strains differing in their level of sexual vigor, there is a sequence from heterogamic to homogamic mating. It is proposed that, by reducing mating speed, inbreeding changes the rate of this sequence but not its pattern, so the apparent level of heterogamic mating will increase during inbreeding, for a fixed observation period. This hypothesis was tested using the Kence-Bryant model of mating success.
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    Preference for ethanol inDrosophila melanogaster associated with the alcohol dehydrogenase polymorphism (1979)
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    Behavior genetics 9 (1979), S. 359-365 
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    ISSN: 1573-3297
    Keywords: ethanol preference ; ADH ; behavior ; genetics ; Drosophila ; Adh electromorphs ; oviposition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Psychology
    Notes: Abstract Two alcohol dehydrogenase genotypes (Adh F /Adh F andAdh S /Adh S ) exhibit different behavioral responses when presented with a choice between ethanol and nonethanol environments at the larval stage but not at the adult stage. The larval preferences are correlated with alcohol dehydrogenase activity, which also differs between genotypes. Since ethanol is important in the ecology of this species, the preference may be related to microhabitat selection in nature.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01066974
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  • 42
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    Genetic analysis of lines selected for wing vibration inDrosophila melanogaster (1979)
    Springer
    Behavior genetics 9 (1979), S. 579-584 
    Details
    ISSN: 1573-3297
    Keywords: Drosophila ; courtship behavior ; artificial selection ; genetic analysis ; heritability ; wing vibration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Psychology
    Notes: Abstract Selection for the wing vibration component of courtship in the Oregon-R stock ofD. melanogaster was practiced for 44 generations. Selection was successful, indicating that there is genetic variation for the trait in the Oregon-R stock. The mean realized heritability of the trait, based on the first 11 generations of selection, was 15%. Biometrical analysis showed that there is some additive genetic variance for the trait with the possibility of some ambidirectional dominance. No maternal effects for the trait were found.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01067354
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  • 43
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    Adaptiveness of a rare male mating advantage under heterosis (1979)
    Springer
    Behavior genetics 9 (1979), S. 51-54 
    Details
    ISSN: 1573-3297
    Keywords: rare male mating advantages ; sexual selection ; heterosis ; Drosophila
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Psychology
    Notes: Abstract It is shown that minority mating advantages, so commonly observed inDrosophila, would be selectively advantageous in a heterotic system. When an allele is below the equilibrium frequency maintained by heterosis, females mating with that homozygote produce offspring of highest mean fitness.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01067121
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  • 44
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    Electronic Resource
    Genetics of phototactic behavior inDrosophila ananassae, a member of theMelanogaster species group (1979)
    Springer
    Behavior genetics 9 (1979), S. 61-67 
    Details
    ISSN: 1573-3297
    Keywords: phototaxis maze ; sex-linked behavior ; Drosophila ; chromosomal homologies ; species differences
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Psychology
    Notes: Abstract Using Hirsch-Hadler phototaxis mazes, selection for photopositive and photonegative behavior was carried out for 21 generations inDrosophila ananassae. The chromosomes that are important in influencing photomaze behavior inD. ananassae are different from what has been observed for other members of themelanogaster species group, and the differences cannot be entirely attributed to the chromosome rearrangements which have occurred during the evolution of these related species.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01067123
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  • 45
    Electronic Resource
    Electronic Resource
    A maximum likelihood statistical method for analyzing frequency-dependent fitness experiments (1979)
    Springer
    Behavior genetics 9 (1979), S. 7-21 
    Details
    ISSN: 1573-3297
    Keywords: frequency-dependent fitness ; statistical analysis ; logistic regression models ; maximum likelihood estimation ; Drosophila
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Psychology
    Notes: Abstract Experiments on frequency-dependent fitness often consist of forming pairwise mixtures of distinguishable types at several frequency combinations. These mixtures are allowed to undergo competition, after which the performance of each type is enumerated. A statistical method for analyzing such experiments is described in this article. This method, suggested previously for other purposes, is superior to the statistical procedures now commonly employed. It involves the maximum likelihood estimation of parameters for two logistic regression models: one which assumes that fitness is frequency-dependent, the other that fitness is constant over changing frequency. Estimators for both models can be calculated without difficulty using an iterative numerical algorithm implemented in a Fortran computer program available from the authors. Fitting both models allows for the construction of a likelihood ratio statistical test for whichever model is more appropriate. The method is illustrated by application to publishedDrosophila data from differential mating success experiments.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01067118
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  • 46
    Electronic Resource
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    In vitro induced pinocytotic activity by a juvenile hormone analogue in oocytes of Drosophila melanogaster (1979)
    Springer
    Cell & tissue research 203 (1979), S. 241-247 
    Details
    ISSN: 1432-0878
    Keywords: Pinocytotic activity ; Juvenile hormone ; Drosophila ; Oocytes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Pinocytotic activity has been analyzed in Drosophila oocytes following either in vivo or in vitro exposure to horseradish peroxidase. The enzyme tracer gains access to the yolk spheres only when supplied to the oocyte in vivo. In oocytes cultured in vitro, peroxidase remains restricted to the residual coated vesicles and to the tubular profiles formed in excess in the cortical ooplasm. In an attempt to induce peroxidase uptake by oocytes cultured in vitro, various incubations were tested. Among these, hemolymph from both sexes is capable of promoting peroxidase uptake up to a level comparable to that detectable in vivo. On the other hand, fat body extracts fail to promote such cellular activity. Finally, the juvenile hormone analogue ZR-515 is shown to be the only factor required to promote pinocytotic activity under the experimental conditions tested. The observations are interpreted to indicate that vitellogenin has no inductive role on pinocytosis but simply acts by adhering to the forming coated vesicles which in turn are produced by the oolemma in response to the action of juvenile hormone.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00237238
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  • 47
    Electronic Resource
    Electronic Resource
    Analysis of hemodynamic responses to hypothalamic stimulation in waking animals (1979)
    Springer
    Bulletin of experimental biology and medicine 88 (1979), S. 981-983 
    Details
    ISSN: 1573-8221
    Keywords: Hypothalamic stimulation ; hypertension ; baroreceptor reflexes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Experiments on waking cats showed that electrical stimulation of “protective” zones of the hypothalamus leads to development of hypertension and inhibits baroreceptor reflexes. In animals with divided carotid sinus and aortic nerves, threshold hypothalamic stimulation leads to the appearance of depressor responses, whereas above-threshold stimulation evoked depressor-pressor responses. It is suggested that depression of baroreceptor reflexes is one of the mechanisms of the development of hypertension in response to hypothalamic stimulation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00799259
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