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  • Articles  (49)
  • spermatozoa  (49)
  • Wiley-Blackwell  (49)
  • American Chemical Society
  • 1980-1984  (49)
  • Biology  (49)
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  • Articles  (49)
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  • Wiley-Blackwell  (49)
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  • Biology  (49)
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  • 1
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 1 (1981), S. 349-362 
    ISSN: 0886-1544
    Keywords: Ca2+ ; flagella ; symmetry ; vanadate ; spermatozoa ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Increased Ca2+ concentration causes a reversible increase in asymmetry of the flagellar bending waves of “potentially symmetric” demembranated sea urchin spermatozoa. When these flagella are immobilized with 5 μM vanadate, increased Ca2+ concentration causes a reversible increase in the total bend angle between the tip and the base of the immobilized flagella. These effects of Ca2+, and the movement which can be activated by CaATP2-, can be inhibited by vanadate, but in both cases, high concentrations of vanadate, of the order of 100 μM, are required. These observations suggest that ATP, possibly in the form of CaATP2-, is required for the Ca2+-induced change in shape of the flagella, but other observations suggest that the magnitudes of asymmetry and total bend angle are more closely related to Ca2+ concentration than to CaATP2- concentration.
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  • 2
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 4 (1984), S. 417-430 
    ISSN: 0886-1544
    Keywords: flagella ; image analysis ; microcomputer ; motility ; parameter estimation ; Simplex method ; spermatozoa ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Parameters to describe flagellar bending patterns can be obtained by a microcomputer procedure that uses a set of parameters to synthesize model bending patterns, compares the model bending patterns with digitized and filtered data from flagellar photographs, and uses the Simplex method to vary the parameters until a solution with minimum root mean square differences between the model and the data is found. Parameters for Chlamydomonas bending patterns have been obtained from comparison of shear angle curves for the model and the data. To avoid the determination of the orientation of the basal end of the flagellum, which is required for calculation of shear angles, parameters for sperm flagella have been obtained by comparison of curves of curvature as a function of length for the model and for the data. A constant curvature model, modified from that originally used for Chlamydomonas flagella, has been used for obtaining parameters from sperm flagella, but the methods can be applied using other models for synthesizing the model bending patterns.
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  • 3
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 3 (1983), S. 247-259 
    ISSN: 0886-1544
    Keywords: spermatozoa ; Ciona ; axoneme ; quiescence ; twist ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: A simple planar model of sliding can predict the amount of sliding required to form a certain degree of bend. The accuracy of this prediction relies on the assumptions that no twists occur in the axoneme and that no sliding occurs at the base. However, previous studies indicated that twists may occur.This paper explores a new method for quantitating and analyzing twists. Preliminary results using this method showed that there were twists. In order to control for possible artifacts due to fixation and other preparative procedures, the characteristic S-shaped quiescent state of Ciona spermatozoa was studied.Analyses of platinum replicas of those flagella in which this waveform is well preserved suggest that most, if not all, of the twists observed are due to the artifact of a curved shape settling onto a surface. Detailed analyses indicate that if twists do occur in quiescent sperm, they are probably less than 0.4 radian. Since axonemes are evidently easily twisted in rigor, and even after fixation, caution should be exercised in interpretation of axonemal twists.
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  • 4
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 2 (1982), S. 225-242 
    ISSN: 0886-1544
    Keywords: spermatozoa ; calcium ion transport ; motility regulation ; cholinergic agonists ; ouabain ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Behavioral responses of mature spermatozoa treated with neurotropic factors suggest that calcium entry and intracellular transport may be regulated by a cholinergic mediated program. To test the validity of this proposed mechanism, the effect of several agents on Ca distribution in the sperm cell was examined cytochemically.Sites of Ca accumulation were visualized in thin sections of bull spermatozoa by the application of a modification of Gomori's histochemical procedure for phosphatases. Intact bull sperm cells incubated at room temperature in a buffered balanced salt solution containing 5 mM/liter of CaCl2 showed small, randomly scattered deposits of the reaction product. Similarly treated sperm cells, plasmolyzed in hypoosmotic KCl, revealed a greatly increased amount of deposit associated with the cell membranes (mitochondrial surfaces and plasmalemma), the axonemal complex components, and satellite fibers adjacent to the outer dense fibers. Preincubation of intact cells in nicotine or eserine considerably enhanced the entry of calcium into the cell and its association with the membranes and other intracellular organelles. Decamethonium, an irreversible depolarizer and blocker of cholinergic receptors, interfered with the uptake and intracellular distribution of the calcium. Ouabain, the digitalis glycoside that decreases progressive motility of bull sperm and inhibits Na-, K-ATPase, appears to block Ca efflux, causing an intense accumulation of electron-opaque particles in the plasma membrane while smaller numbers of particles are distributed sparsely throughout the cell interior.The cytochemical results showing enhanced calcium entry in the presence of cholinergic agents, depressed intracellular calcium in cells treated with cholinergic receptor blocker, and intense accumulation of calcium within the cell membrane in the presence of ouabain are consistent with spermatozoan behavioral responses to these agents. These observations support the concept that neurotropic factors may be involved in regulating transmembrane and intracellular transport of ions in control of sperm cell function.
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  • 5
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Gamete Research 4 (1981), S. 57-63 
    ISSN: 0148-7280
    Keywords: taurine ; hypotaurine ; spermatozoa ; in vitro fertilization ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Taurine and hypotaurine were examined for their efficacy in replacing sperm motility factor (SMF), prepared from bovine adrenal cortex, for in vitro fertilization in the golden hamster. Combinations of these amino acids at concentrations of 0.001, 0.01, 0.1, and 1 mM together with 16 μM isoproterenol (a catecholamine β-agonist) were added to the sperm incubations. After three hours of sperm preincubation, oviductal eggs were added to the sperm suspensions and examined for penetration and stage of fertilization after three or five hours of culture. At 0.001 mM, neither taurine or hypotaurine was capable of maintaining motility of hamster sperm for four to 4½ hours or of inducing fertilization. With all other concentrations, both amino acids were found to maintain motility of sperm as well as SMF. Hypotaurine stimulated motility to a greater extent than taurine and both required isoproterenol for the greatest motility. A low proportion of cumulus-free ova were fertilized when sperm were preincubated with either amino acid alone over the range of 0.01 to 1 mM; however, over 80% fertilization was consistently obtained when isoproterenol was also present during sperm incubation. Proportions of ova fertilized with taurine or hypotaurine present during sperm preincubation were comparable to those achieved with SMF. The possibility that taurine or hypotaurine is the sperm motility factor is discussed.After three hours of sperm/egg incubation, a lag in the early events of fertilization was observed in experimental groups treated with one of the amino acids (0.01 mM) alone compared with groups treated with isoproterenol present. However, if sperm/egg incubation was extended from three to five hours, no increase in number of eggs penetrated was found. Therefore, the delay observed at three hours was considered a function of fewer numbers of capacitated sperm present in the absence of isoproterenol rather than of the need for an extended capacitation time.
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  • 6
    ISSN: 0148-7280
    Keywords: capacitation ; acrosome reaction ; fertilization ; lysophospholipids ; spermatozoa ; membrane fusion ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The effects of lipids on the survival, acrosome reaction, and fertilizing capacity of guinea pig spermatozoa were studied by incubating the spermatozoa in media containing various concentrations of the lipids. Lipids tested were: phosphatidyl-choline (PC), -ethanolamine (PE), -inositol (PI), -serine (PS), sphingomyelin (S), cholesterol (C), lysophosphatidyl-choline (LC), -ethanolamine (LE), -inositol (LI), -serine (LS), and glyceryl monooleate (M).When spermatozoa were incubated in a regular medium (containing 2 mM Ca2+) with M, the majority underwent the acrosome reaction within 1 hour. None of the other lipids were as effective as M, and some were totally ineffective under the same conditions. However, when spermatozoa were preincubated in Ca2+-free medium containing LC, LE, or LI, they gained the ability to undergo the acrosome reaction. One hour of preincubation in Ca2+-free medium with LC, LE, or LI was enough to render the vast majority of spermatozoa capable of undergoing the acrosome reaction in response to Ca2+. The optimum concentrations for LC, LE, and LI were approximately 85 μg/ml, 210 μg/ml, and 140 μg/ml, respectively. Spermatozoa that had undergone the acrosome reaction by pretreatment with LC, LE, or LI remained actively motile and were capable of fertilizing eggs. LS was totally ineffective in rendering the spermatozoa capable of undergoing the acrosome reaction, and in fact it inhibited the acrosome reaction by itself and also inhibited the LC-, LE-, or LI-mediated acrosome reaction. LS did not prevent acrosome-reacted spermatozoa from penetrating the zona pellucida, but did prevent sperm-egg fusion.Based on these findings, it is suggested that lysophospholipids are intricately involved in the sperm acrosome reaction and perhaps in sperm-egg fusion.
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  • 7
    Electronic Resource
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    New York, NY : Wiley-Blackwell
    Gamete Research 4 (1981), S. 275-282 
    ISSN: 0148-7280
    Keywords: spermatozoa ; activation ; oviduct ; sperm movements ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Spermatozoa were flushed with mineral oil from the lower isthmus of the rabbit oviduct at four hours postcoitus (pc) and 11 hours pc. Videotapes were made of sperm behavior in the native isthmic fluid and after dilution of the fluid with culture medium. The tapes showed that, initially, spermatozoa in the native isthmic fluid were virtually immotile, but immediately resumed movement on contact with the culture medium. Isthmic sperm motility then evolved over a five- to 10-minute interval into the characteristic biphasic pattern of activated movement. Cine films of isthmic spermatozoa taken with a high-speed camera were analyzed to determine flagellar beat frequency, maximum flagellar curvature, and swimming velocity. Progressiveness ratios and hydrodynamic power outputs were then calculated for individual spermatozoa. Two phases of activated sperm movement, a whiplash phase and a progressive phase, were identified and characterized. The power output of activated spermatozoa increased twentyfold in comparison with the preactivated state. The power output of activated spermatozoa did not differ between the two phases of activated movement.
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  • 8
    Electronic Resource
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    New York, NY : Wiley-Blackwell
    Gamete Research 4 (1981), S. 283-295 
    ISSN: 0148-7280
    Keywords: spermatozoa ; rat ; epididymis ; motility ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Experiments were performed to further the understanding of epididymal processes involved in the acquisition of sperm motility. Samples of luminal contents were collected by micropuncture from four regions of the rat epididymis. These samples were incubated in various diluents to observe the effects of the diluents on sperm motility. Consonant with previous reports, 40 mM glycerylphosphorylcholine (GPC) and 60 mM DL-carnitine reduced overall motility scores of cauda epididymidal spermatozoa but did not prevent normal initiation of motility. Additionally, control sperm cells and cells treated with carnitine could reinitiate full motility after becoming immotile. Spermatozoa treated with GPC could not reinitiate motility. The sperm cells in our system thus react to GPC and carnitine in fundamentally different ways, the exact nature of which remains to be determined.Spermatozoa from the distal caput epididymidis evidenced high motility scores when diluted in a 5% egg yolk + 10 mM caffeine diluent. It was demonstrated, however, that the subjective appearance of full motility in these immature cells was not supported by actual progressive motility as measured in an assay of linear distance traveled. It was concluded that neither 10 mM caffeine, 5% egg yolk, nor their combination was sufficient to induce progressive motility in immature rat spermatozoa.
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  • 9
    Electronic Resource
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    New York, NY : Wiley-Blackwell
    Gamete Research 5 (1982), S. 153-160 
    ISSN: 0148-7280
    Keywords: zinc ; capacitation ; spermatozoa ; human ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The effects of zinc on human sperm motility, fertilizing capacity (as assessed by penetration of human spermatozoa into the zona pellucida-free hamster oocyte), and nuclear chromatin decondensation were investigated using spermatozoa from four fertile donors. Both sperm motility and the penetration of sperm into zona-free hamster ova were consistently impaired in media containing 1,000 μM zinc. Spermatozoa from one man were similarly affected at a concentration of 500 μM zinc, but no adverse effects were noted at this zinc concentration in experiments with other donors. Since decreased fertilizing capacity in response to zinc was always accompanied by a significant decline in both the percentage of motile cells and mean swimming speeds, it appears that all of these results reflect a general toxic effect on the cells. At lower concentrations (125-250 μM), zinc had no effect on human sperm motility nor their ability to undergo capacitation and penetrate zona-free hamster ova in vitro. For some donors, zinc (125-500 μM) stimulated both the attachment of spermatozoa to the hamster vitellus and the incorporation of spermatozoa into the hamster ooplasm. The decondensation of human sperm nuclear chromatin in sodium dodecyl sulfate was largely inhibited when zinc was added to the medium, but no significant changes in nuclear stability were apparent after capacitation in zinc-free medium. We conclude that zinc, when present in subtoxic concentrations, does not adversely affect the ability of human spermatozoa to undergo capacitation and penetrate zona-free hamster ova in vitro.
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  • 10
    Electronic Resource
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    New York, NY : Wiley-Blackwell
    Gamete Research 4 (1981), S. 407-432 
    ISSN: 0148-7280
    Keywords: acrosin ; acrosome reaction ; calcium ; hyaluronidase ; ionophore ; spermatozoa ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: A system has been developed for inducing a calcium-dependent acrosome reaction in ram spermatozoa in vitro using the calcium ionophore A23187. The resultant reaction is accompanied by release of the acrosomal enzymes hyaluronidase and acrosin, but there is no release of the cytoplasmic enzyme glucose 6-phosphate isomerase. In any given cell, the visible acrosome reaction apparently takes place rapidly, but there is a variable delay before the reaction occurs. Under optimum conditions, about 90% of treated spermatozoa show an acrosome reaction within one hour.Preincubation of the spermatozoa with the proteinase inhibitors p-amino-benzamidine or p-nitrophenylguanidinobenzoate allows two stages of the reaction to be distinguished ultrastructurally, a membrane fusion stage followed by a dispersal of the acrosomal matrix. In the presence of the inhibitors, the first stage is delayed but is completed within 1 hour, whereas the second remains largely incomplete.In the presence of calcium, ionophore concentrations which induce an acrosome reaction abolish sperm motility rapidly and completely. However, by adding serum albumin shortly after addition of ionophore, motility can be preserved while the acrosome reaction occurs as usual; the motility pattern observed under these conditions is of the “whip-lash” or “activated” type.Although the motile ionophore-treated spermatozoa were unsuccessful at penetrating normal mature sheep oocytes in vitro, they were able to penetrate zona-free oocytes, after which swelling and decondensation of the sperm head took place.
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  • 11
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    New York, NY : Wiley-Blackwell
    Gamete Research 5 (1982), S. 61-70 
    ISSN: 0148-7280
    Keywords: mouse ; spermatozoa ; concentration ; fertilization ; ova ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The effect of varying the sperm concentration between 2 × 105 sperm/ml and 8 × 106 sperm/ml on fertilization of cumulus-free, zona-intact F1 (CBA × C57BL) mouse ova by QS and F1 (CBA × C57BL) mouse spermatozoa was studied. The spermatozoa from both strains of mice exhibited optimal fertilization rates at 2 × 106 sperm/ml. However, at sperm concentrations greater than 4 × 106 sperm/ml and less than 1 × 106 sperm/ml, fertilization rates were significantly reduced. F1 spermatozoa were more susceptible to dilution than QS spermatozoa. A significant interaction between strain and sperm concentration indicated that the two strains produced different fertilization rates at different sperm densities.Extracts of epididymal fluid, medium from capacitated spermatozoa, or ampulla fluid did not improve the fertilization rate at 2 × 105 sperm/ml, but retaining the cumulus oophorus did. The decrease in fertilization rate at 8 × 106 sperm/ml can in part be attributed to a nondialysable inhibitor from the neat sperm preparation that appeared to be of epididymal origin.
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  • 12
    Electronic Resource
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    New York, NY : Wiley-Blackwell
    Gamete Research 6 (1982), S. 343-352 
    ISSN: 0148-7280
    Keywords: acrosome reaction ; spermatozoa ; oviducal extract ; toad ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The acrosome in the sperm of the toad, Bufo bufo japonicus, consists of a membrane-limited acrosomal cap and a fibrous perforatorium. When sperm are incubated with the oviducal pars recta extract (PRE) for 30-60 min, the outer acrosomal membrane fuses with the overlying plasma membrane at several points with concomitant loss of the contents of the acrosomal cap. The inner acrosomal membrane thus exposed fuses with the plasma membrane at the caudal end of the acrosomal region. This PRE-induced acrosome reaction is completely inhibited by soybean trypsin inhibitor. Sperm found in the innermost jelly layer of inseminated eggs possess an intact acrosome, but those either passing through the vitelline coat or localizing in the perivitelline space are acrosome-reacted in the same manner as when treated with PRE. These observations, combined with recent evidence showing involvement of the pars recta substance in fertilization, indicate that the acrosome reaction occurring in a fertilizing sperm at or near the surface of the vitelline coat is a response to a substance that is derived from the pars recta and deposited in the vitelline coat.
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  • 13
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    New York, NY : Wiley-Blackwell
    Gamete Research 8 (1983), S. 201-218 
    ISSN: 0148-7280
    Keywords: protein kinase ; cyclic AMP ; phosphorylation ; flagella ; motility ; spermatozoa ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Demembranated spermatozoa of Ciona do not become motile when provided with MgATP, unless their motility is activated in vivo before demembranation or unless the demembranated spermatozoa are activated in vitro with cAMP or with the catalytic subunit of a cAMP-dependent protein kinase. CAMP causes a greater than fivefold enhancement of 32P incorporation by demembranated spermatozoa. Analysis by one-dimensional PAGE and autoradiography shows several axonemal protein bands that become 32P-labeled during in vitro activation with cAMP and identifies protein bands whose labeling is specifically reduced if motility of the spermatozoa is activated before demembranation, suggesting that these proteins also become phosphorylated during activation of motolity in vivo. These phosphorylated proteins appear to include dynein heavy-chain components, but axonemal tubulin is not phosphorylated. Partially phosphorylated spermatozoa can be activated by an increase in KCI concentration, which appears to dissociate one phosphorylated component from the axoneme.
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  • 14
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    New York, NY : Wiley-Blackwell
    Gamete Research 9 (1984), S. 115-125 
    ISSN: 0148-7280
    Keywords: acrosome reaction ; fertilization ; sea urchin ; spermatozoa ; surfactants ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The effects of seven surfactants on spermatozoa of the sea urchin, Hemicentrotus pulcherrimus, were studied. All these surfactants induced the acrosome reaction and inhibited the fertilizing capacity of spermatozoa. There was a statistically significant correlation between the concentrations that induce the acrosome reaction and inhibit fertilization. The critical micelle concentrations (CMC) of surfactants in sea water were almost even and these values, which are inherent physical properties of surfactants, did not provide a direct measure of their inhibitory effect of fertilization. Among seven surfactants, p-menthanyl-phenol polyoxyethylene (8.8) ether (TS-88) with a characteristic hydrophobes was the most potent both in the induction of acrosome reaction and in the inhibition of fertilization. Various ethylene oxide adducts to p-menthanyl-phenol were also tested for the purpose of comparison. It is suggested that the effects of surfactants on sea urchin spermatozoa at low concentrations reflect their activity associated with the hydrophobic group inherent in each surfactant.
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  • 15
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    New York, NY : Wiley-Blackwell
    Gamete Research 9 (1984), S. 425-440 
    ISSN: 0148-7280
    Keywords: acrosin ; acrosome reaction ; enzyme localization ; immunocytochemistry ; proacrosin ; spermatozoa ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Proacrosin and acrosin were localized immunocytochemically at the electron microscope level in ram spermatozoa undergoing an ionophore-induced acrosome reaction. Antigenicity was preserved after fixation with 0.5% w/v ethyl-(dimethylaminopropyl)-carbodimide, and an antibody preparation was used that reacted with all major forms of ram acrosin. All stages of the acrosome reaction could be observed in a single preparation. At the earliest stage, labeling was observed throughout the acrosomal contents, which were just beginning to disperse. As dispersal proceeded, labeling diminished, being associated only with visible remnants of the acrosomal matrix. By the time the acrosome had emptied, almost no labeling could be detected on the inner acrosomal membrane.The relationship between matrix dispersal and proacrosin activation was studied in isolated ram sperm heads. While proacrosin was prevented from activating, the acrosomal matrix remained compact; but as activation proceeded, the matrix decondensed and dispersed in close parallel. By the time proacrosin activation was complete, the acrosomal contents had almost entirely disappeared.We conclude that proacrosin is distributed throughout the acrosomal contents as an intrinsic constituent of the acrosomal matrix. During the acrosome reaction, proacrosin activation occurs, resulting directly in decondensation of the matrix. All the contents of the acrosome including acrosin disperse and, by the time the acrosome is empty and the acrosomal cap is lost, only occasional traces of acrosin remain on the inner acrosomal membrane. Since the acrosomal cap is normally lost during the earliest stages of zona penetration, acrosin's role in fertilization is unclear: it does not appear to be a zona lysin bound to the inner acrosomal membrane.
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  • 16
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    Gamete Research 10 (1984), S. 1-8 
    ISSN: 0148-7280
    Keywords: spermatozoa ; acrosome ; aerosome reaction ; sperm motility ; guinea pig ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The effect of pH on both motility and the acrosome reaction of guinea pig spermatozoa was examined by transferring fully capacitated spermatozoa from Ca2+ -free medium to Ca2+ -containing media with various pH values (8.2, 7.5, 7.0, 6.7, 6.4, and 6.1). When transferred to media of pH 7.5 or 8.2, the spermatozoa underwent their acrosome reactions to the maximum level within 15-20 min. Acrosome-reacted spermatozoa were vigorously motile. The intensity of sperm motility and the incidence of the acrosome reaction declined with decreasing pH values. At pH 6.1, the motility of all the spermatozoa quickly became very weak. No acrosome reactions occurred at this low pH. The inhibition of motility and the acrosome reaction at pH 6.1 was reversed by transferring the spermatozoa back to the alkaline medium unless they were exposed to this low pH for longer than 3 hr. The inhibition of the acrosome reaction at low pH values (other than 6.1) was counteracted to some extent by increased concentrations of Ca2+ (4-10 mM). Possible mechanisms by which low pH reversibly inhibits sperm motility and the acrosome reaction are discussed.
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  • 17
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    Gamete Research 10 (1984), S. 233-239 
    ISSN: 0148-7280
    Keywords: chromosome ; spermatozoa ; sperm ; egg ; zona-free ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: An improved method for human sperm chromosome preparation is described. Improvements include (1) the use of a sperm population with high motility and normal morphology for insemination, (2) the insemination and postinsemination culture of zona-free eggs in Holmes medium, which does not require serum supplementation, (3) control of sperm concentration at insemination to avoid heavy polyspermy, (4) reduction of the occurrence of egg agglutination by placing the medium for postinsemination culture in a ring or crescent shape instead of a droplet, and (5) application of a two-step fixation method to augment the efficiency of chromosome preparation.
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  • 18
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    Gamete Research 10 (1984), S. 253-265 
    ISSN: 0148-7280
    Keywords: sperm motility ; hyperactivation ; acrosome reaction ; spermatozoa ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: High-speed videomicrography was used to compare the movement characteristics of hamster epididymal sperm which completed the acrosome reaction in vitro with those of unreacted sperm in the same sample. More than 90% of the motile sperm incubated for 4.25 hr in a modified Tyrode's medium containing bovine serum albumin, taurine, and epinephrine were hyperactivated and about half were acrosome reacted. The flagella of reacted sperm beat with significantly lower frequency and bent into more acute curves than those of unreacted sperm. Lowered beat frequencies were not attributable to aging, because sperm induced to react synchronously at 3.5 hr using lysophosphatidyl choline beat with similar lowered frequencies. Both acrosome-reacted and unreacted hyperactivated sperm swam in circular trajectories resulting from asymmetrical flagellar beating. The flagellar beating of unreacted sperm was more symmetrical; consequently, they swam in larger circles and had the potential to cover space more rapidly. Some unreacted sperm, perhaps in transition towards hyperactivation, swam in helical trajectories.When preincubated sperm were added to slides containing oocytes in cumulus, some unreacted sperm initiated cumulus penetration. All reacted sperm failed to do so, adhering instead to the cumulus at its boundary. Reacted sperm attached to the zonae pellucidae of cumulus-free oocytes via the region of the inner acrosomal membrane. Unreacted sperm attached via the equatorial region, but pivoted about the point of attachment, thus failing to generate sustained thrust against the zona. In conclusion, unreacted hyperactivated sperm have a different potential than reacted sperm for movement and interaction with egg vestments.
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  • 19
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    Gamete Research 10 (1984), S. 283-299 
    ISSN: 0148-7280
    Keywords: Mouse ; spermatozoa ; cyclic nucleotides ; adenylate cyclase ; phosphodiesterase ; capacitation ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The role of cyclic nucleotides in sperm capacitation is equivocal. Using conditions known to support mouse sperm capacitation after 120 min incubation in vitro, the cAMP and cGMP contents of epididymal spermatozoa were measured and the cGMP/cAMP ratio determined. The initial high cAMP content detected upon release of spermatozoa decreased within 30 min to a lower plateau, which was then maintained throughout incubation. With the cGMP content remaining approximately constant, the cGMP/cAMP ratio increased over 120 min. In the presence of 2 mM caffeine, an increased cAMP content was noted at 0 and 30 min before a fall to the plateau level. To investigate cyclic nucleotide metabolism, adenylate cyclase and phosphodiesterase activities were compared in two sperm populations, one essentially uncapacitated and the other incubated for 120 min. Adenylate cyclase activity, higher in the presence of 2 mM Mn2+ compared to Mg2+, showed increased activity at 120 min compared to 30 min incubation, while phosphodiesterase activity decreased during this period. The ability of spermatozoa to form adenosine and inosine from cAMP indicated endogenous 5′-nucleotidase and deaminase, as well as phosphodiesterase, activities. Although the endogenous cAMP content appeared to remain constant during the time that acrosome loss, hyperactivated motility and fertilizing ability can be demonstrated, activities of the enzymes responsible for cAMP metabolism indicate an increased potential for cAMP availability and turnover. The increased cGMP/cAMP ratio may also play a role during capacitation.
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  • 20
    ISSN: 0148-7280
    Keywords: spermatozoa ; flow cytometry ; DNA staining ; nuclear morphology ; ultrastructure ; mammals ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The morphological and ultrastructural changes that occur during preparation of porcine, bovine, and murine spermatozoa for flow cytometric quantification of the relative DNA content of the X- and Y-chromosome-bearing sperm populations were examined. Ejaculated spermatozoa from the boar and bull were washed using a series of dimethyl sulfoxide (DMSO) solutions prior to fixation, whereas the epididymal mouse spermatozoa were washed only in phosphate-buffered saline (PBS). Spermatozoa from all three species were then fixed in ethanol and processed for fluorochrome staining by a treatment regimen consisting of sulfhydryl reduction and proteolysis. The processed sperm nuclei were stained for DNA with the fluorochrome, 4′-6-diamidino-2-phenylindole (DAPI) before quantification by flow cytometry. Scanning and transmission electron micrographs of sperm heads taken at various steps of the preparation and staining procedures show 1) that the rigorous washing procedure disrupted the plasma and outer acrosomal membranes, 2) that ethanol fixation resulted in removal of the outer membranes and disintegration of the nuclear envelope, and 3) that thiol and proteolysis treatment removed the remaining cellular organelles including the tail and rapidly induced partial decondensation of the tightly packed chromatin. Sequential micrographs showed that the nuclear matrix of all three species increased in thickness about twofold during the preparation and staining. Consequently, the harsh procedures currently used for quantitative staining of DNA for high-resolution flow cytometric analyses destroy most cellular organelles and thereby prevent simultaneous characterization of DNA content and other sperm cell constituents.
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  • 21
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    Gamete Research 4 (1981), S. 15-23 
    ISSN: 0148-7280
    Keywords: secretory IgA ; oviduct fluid ; acrosin ; spermatozoa ; fertilization ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: A major inhibitor of acrosin in rhesus monkey and rabbit oviduct fluid, isolated by isoelectrofocusing in sucrose gradients, displayed a broad peak in the acidic region of the column and was demonstrated to contain secretory IgA specific for acrosin. Its identity was established by immunodiffusion, by the removal of acrosin inhibition with antisera to IgA (α-chain), and by its correct molecular weight during ultracentrifugation. Purified human serum IgA also inhibited rabbit, rhesus monkey, and human acrosins, but neither purified human IgG nor IgM had any inhibitory effect on these acrosins. Neither oviduct fluid secretory IgA nor purified human serum IgA inhibited the activity of bovine pancreatic trypsin. The high specificity of secretory IgA for acrosin and its presence in every rabbit and rhesus monkey oviduct fluid specimen examined suggests a possible regulatory role for this antibody in reproduction.
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  • 22
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    Gamete Research 4 (1981), S. 525-533 
    ISSN: 0148-7280
    Keywords: capacitation ; fertilization ; spermatozoa ; in vitro ; Little Brown Bat ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The temperature dependence of capacitation in bat sperm (Myotis lucifugus lucifugus) was studied by monitoring fertilizations rates of zona-free hamster ova at different temperatures. Spermatozoa were cultured in BWW medium at temperatures 4°C, 24°C, 32°C, 42°C, and 55°C from 0-24 hr. Activation of sperm could be determined visually due to the change in movement seen through light microscopy. Activation was later confirmed by higher rates of fertilization. Preincubation of the bat sperm was found to have a direct effect on the success of penetration of the zona-free hamster ova. Holding bat spermatozoa at low temperature for long intervals allowed them to remain motile but unable to fertilize. Sperm are not irreversibly damaged, however, and activation, when the temperature is increased to 32°C, is faster than when sperm are intitially put at 32°C, resulting in good fertilization rates.
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  • 23
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    Gamete Research 5 (1982), S. 263-269 
    ISSN: 0148-7280
    Keywords: spermatozoa ; bull ; rolled sperm ; crested sperm ; knobbed sperm ; testis ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The ejaculate of a Friesian bull contained three abnormalities: rolled, crested, and knobbed spermatozoa. The rolled form had marked lateral curvature of the head, occasionally forming a complete tube. All three forms were of testicular origin and it is likely that the first two were developmentally related.
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  • 24
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    Gamete Research 5 (1982), S. 323-344 
    ISSN: 0148-7280
    Keywords: calcium ; fertilization ; spermatozoa ; eggs ; hamster ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Using a semi-chemically defined medium, the requirement of extracellular Ca2+ for survival, capacitation, and acrosome reaction of spermatozoa as well as various stages of fertilization in the hamster was studied. A Ca2+-deficient environment is unfavorable for long-term survival of spermatozoa. Sperm capacitation may occur in Ca2+-deficient media, but not as efficiently as in normal media. The acrosome reaction definitely requires extracellular Ca2+. Other processes or phenomena that require extracellular Ca2+ are initiation and maintenance of hyperactivated motility of spermatozoa, penetration of acrosome-reacted spermatozoa into the zona pellucida, fusion of the spermatozoa with eggs, and the development of pronuclear eggs into two-cell embryos. Extracellular Ca2+ is apparently unnecessary for the attachment of spermatozoa to the zona and egg surfaces, decondensation of the sperm nucleus, and the development of sperm and egg pronuclei within the egg. These results were compared with data obtained in other species such as the sea urchin, mouse, rat and guinea pig.
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  • 25
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    Gamete Research 5 (1982), S. 217-227 
    ISSN: 0148-7280
    Keywords: spermatozoa ; bull ; stallion ; vitelli ; hamster ; fertilization ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Zona-free hamster ova interacted with bull and stallion spermatozoa after treatment of ejaculated semen to capacitate the sperm cells. Sperm conditioning by prolonged incubation in BWW medium (18-26 hr) prior to insemination was effective for capacitation of bull and stallion sperm. Preincubation of bull sperm for 70 or 105 min in defined medium (DM) with NaCl content elevated to result in 350 m0sM/kg also led to penetration of hamster vitelli. More rapid sperm conditioning was possible and higher proportions of interacting vitelli followed insemination with bull or stallion sperm exposed to high ionic strength DM (380-390 m0sM/kg) for 10 min before incubation in isotonic DM prior to insemination, the treatment adopted in subsequent work.Initial efforts to assess relative fertilizing ability of freshly ejaculated semen from two fertile bulls (A and B) in A1 usage resulted in uniformly high ( 〉 90%) levels of sperm-vitelli interaction (for both) when the hamster ova employed resulted from superovulation with PMSG and HCG. Following use of ova from untreated hamsters sperm samples of bull A and bull B interacted with 53.8% and 84.9% (P 〈 0.05) of zona-free hamster ova, respectively. Conception data (60-90 day nonreturn rates) resulting from A1 with semen collected during the same interval but processed and stored in liquid nitrogen prior to use revealed an inverse relationship to proportions of vitelli interacting with fresh sperm; nonreturn rates were 69.3% and 66.3% for bull A and bull B, respectively. A similar treatment effected capacitation of frozen-stored bull semen to enable sperm-vitelli interaction. These findings encourage additional efforts to correlate testing of processed semen with fertility.
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  • 26
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    Gamete Research 5 (1982), S. 355-361 
    ISSN: 0148-7280
    Keywords: fucose ; fucoidin ; spermatozoa ; zona pellucida ; recognition ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Experiments were designed to test the effects of simple sugars and complex polysaccharides on the attachment of mammalian spermatozoa with the zona pellucida. In the guinea pig, L-fucose was a twofold better inhibitor of the attachment compared to other sugars at 50 mM. Fucoidin, an algal polysaccharide rich in sulfated L-fucose, was a very potent inhibitor, completely blocking attachment at a concentration of 100 μg/ml. Several other highly sulfated glycosaminoglycans showed no inhibitory activity, suggesting the fucoidin effect was not simply due to its charge or sulfate. In addition, fragments of fucoidin, generated by partial hydrolysis and isolated using Biogel P-2, were nearly as inhibitory as the native molecule on a weight basis. Fucoidin also inhibited sperm-zona attachment in the hamster and human; thus, its effect is not species specific. The data suggest that L-fucose may be part of a recognition signal between mammalian gametes.
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  • 27
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    Gamete Research 5 (1982), S. 379-393 
    ISSN: 0148-7280
    Keywords: circular DNA ; spermatozoa ; human ; boar ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Circular DNA molecules were isolated from human and boar whole spermatozoa or spermatozoal nuclei and measured for size by electron microscopy. The DNA molecules derived from both mammals were heterogeneous in size ranging from 0.07 to 17 μm; nearly 75% of the molecules were ≤0.5 μm in length. The mean lengths were 1.0 μm and 1.5 μm for circular DNAs isolated from human and boar spermatozoa, respectively. The origin and function of these molecules remains unknown.
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  • 28
    ISSN: 0148-7280
    Keywords: epididymis ; ram ; spermatozoa ; zona pellucida ; rat ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: To assess the ability of ram spermatozoa to bind to oocytes, spermatozoa (2.5-200 × 106/500μ1) taken from the rete testis, or from various regions of the epididymis (head, body, and tail) were mixed with cumulus-free heterologous oocytes obtained from immature superovulated rats. After incubation for 30-45 min in Parker 199 Hepes medium at 35°C, testicular spermatozoa were unable to bind to the zona at any of the concentrations used. However, spermatozoa from the middle body of the epididymus were able to bind to the zona and this binding reached a maximum in the distal body and in the tail of the epididymis. The spermatozoa were bound by their heads. Electron microscopy showed that the plasma membrane and the acrosome of the bound sperm remained intact, without any sign of an acrosome reaction.
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  • 29
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    Gamete Research 7 (1983), S. 367-376 
    ISSN: 0148-7280
    Keywords: spermatozoa ; erythrocytes ; epididymis ; proteins ; sperm binding ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Tissue pieces from the caput epididymidis of the rat were incubated in vitro with (35S) methionine to produce radioactive secretory proteins. The radioactive secretory proteins so formed were tested for their ability to bind to washed rat spermatozoa collected from the rete testis and cauda epididymidis, and to rat erythrocytes. The sperm and erythrocytes bound approximately 5% of the total radioactive protein. Binding was protein-specific in that only selected proteins became associated with the cells. Binding was not cell-specific, however, since testicular spermatozoa, caudal spermatozoa, and erythrocytes all bound the same proteins to a similar degree.
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  • 30
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    Gamete Research 7 (1983), S. 63-73 
    ISSN: 0148-7280
    Keywords: effect ; spermatozoa ; mouse ; embryo ; development ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The effects on mouse embryo development in vivo of varying the numbers of spermatozoa used in artificial inseminations was studied. The two criteria used in the evaluation of the progress of embryo development were 1) ability to reach the two-cell stage and 2) success of development from the two-cell stage through implantation. A 44% reduction in the yield of two-cell embryos and a 67% reduction in the number of implants was observed when C3HeB/FeJ females were inseminated with one-twentieth the number of spermatozoa estimated to be present in a typical ejaculate. The reduction in the yield of two-cell embryos was substantially reversed by a second insemination of a large number of heat-inactivated spermatozoa 12 hr after the first insemination. The sperm-dependent reduction in development from the two-cell stage through implantation was prevented only by normal viable (unheated) spermatozoa. These results were rationalized by the hypothesis that in female C3HeB/FeJ mice spermatozoa serve physiological functions beyond the fertilization of ova and that spermatozoa may act to foster early embryo development through modulation of the environments embryos experience as they move through the reproductive tract.
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  • 31
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    Gamete Research 7 (1983), S. 75-84 
    ISSN: 0148-7280
    Keywords: fate ; spermatozoa ; female ; mouse ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Mechanisms were sought through which the control of preimplantation mouse embryo development by spermatozoa might be effected. A potential route for the transmission of sperm-dependent stimuli to C3HeB/FeJ females was uncovered. It was found that within 24-48 hr after artificial insemination with spermatozoa, in which the DNA had been labeled with tritiated thymidine, a minimum of 9% of the radioactivity was transported across the uterine walls. It was deposited among the maternal tissues in a pattern that differed from the patterns of isotope distribution obtained when either free tritiated thymidine or Escherichia coli cells containing DNA labeled with tritiated thymidine were used instead of labeled sper-matozoa. In sperm-treated animals the ovaries, the adrenals, and a mesenteric lymph node exhibited strikingly large accumulations of radioactivity. The heart, spleen, and uterus manifested lesser accumulations of label, but were higher than liver, kidney, lung, brain, muscle, and intestine. The specific activity of the lymph node was found to decrease during the 12-72-hr period following insemination. This result led to the hypothesis that the lymphatic system could serve as a route for the dissemination, to maternal tissues, of radioactivity originally associated with spermatozoa deposited in the uterus. Heat-inactivated spermatozoa, which have the potential for facilitating the first cleavage of fertilized embryos, exhibited a distribution pattern indistinguishable from untreated spermatozoa. Sperm protein kinase was found to survive the heat inactivation of spermatozoa. This stability was interpreted as being compatible with the kinase functioning as an intermediary in the transmission of sperm-dependent stimuli that control preimplantation embryo development in mice.
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  • 32
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    Gamete Research 10 (1984), S. 187-232 
    ISSN: 0148-7280
    Keywords: spermatozoa ; zona-free egg ; egg ; fertilizing capacity ; sperm chromosome ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
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  • 33
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    Gamete Research 8 (1983), S. 255-265 
    ISSN: 0148-7280
    Keywords: antigens ; plasma membrane ; intracellular ; monoclonal antibodies ; spermatozoa ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Fluorescent antibody labeling techniques are frequently used to investigate the topography of antigens on spermatozoa. It is generally assumed that these procedures detect molecules only on the sperm surface but we now show that this assumption is not always valid. Using monoclonal antibodies that recognize either surface or internal antigens we demonstrate how spurious conclusions can be made, and we suggest simple procedures for assigning the position of an antigen to the cell surface or to an intracellular organelle. Antibodies against plasma membrane antigens should stain 100% of normal intact spermatozoa, but this proportion should be greatly reduced if the spermatozoa have previously been demembranated. If ≪ 100% of spermatozoa are stained but the proportion increases following permeabilization, then the possibility should be considered that the antigens are intracellular. We conclude that assignment of an antigen to a regional domain on the sperm surface using fluorescent antibody techniques should be validated by a demonstration that the antigen is actually located on the cell surface.
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  • 34
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    Gamete Research 7 (1983), S. 401-406 
    ISSN: 0148-7280
    Keywords: epididymis ; secretion ; surface protein ; spermatozoa ; reptilian ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: A major soluble protein occurring in two forms, a monomer (protein L) and a polymer, has been identified in the voluminous secretory granules produced by the epithelium of Lacerta vivipara epididymis. An antiserum was raised against protein L and used as an immunohistochemical probe. Indirect immunofluorescence microscopy has indicated that protein L is able to bind to the heads of the spermatozoa. By incubating spermatozoa with buffers of increasing ionic strength and by using nonionic detergents it was not possible to remove completely the protein L. Therefore it was concluded that the binding of protein L to the spermatozoa was not labile and might play an important role in the physiology of the spermatozoa, which is presently under investigation with this convenient model.
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  • 35
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    Gamete Research 9 (1984), S. 1-19 
    ISSN: 0148-7280
    Keywords: spermatozoa ; acrosome ; fertilization ; hamster ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Adult female golden hamsters were induced to superovulate. When they were mated several hours prior to ovulation or artificially inseminated about the time of ovulation, nearly 100% of their eggs were subsequently fertilized monospermically. During the progression of fertilization when the eggs were still surrounded by compact cumulus oophorus, the contents of the ampullary region of the oviducts were collected and spermatozoa moving in the ampullary fluid, within the cumulus and on/in the zonae pellucidae of unfertilized eggs, were examined by light and electron microscopy to evaluate the status of their acrosomal caps.Most spermatozoa swimming in the ampullary fluid had apparently intact acrosomal caps, while the vast majority moving within the cumulus had distinctly modified acrosomal caps. Most spermatozoa that had passed through the cumulus and reached the zona surfaces had remnants of their acrosomal caps (“acrosomal ghosts”). When the ghosts were present around the sperm heads on the zona, the heads pivoted about a point roughly corresponding to the places where the ghosts were located. The ghosts seemed to firmly attach to the zona surfaces, then were split open by the sperm heads and left behind as the sperm heads advanced into the zona. A few spermatozoa on the zona surfaces had no acrosomal ghosts (at least not detectable by light microscopy). In this case, the sperm head pivoted about either the inner acrosomal membrane or the equatorial segment of the acrosome. In no instance were spermatozoa with intact acrosomal caps found on zona surfaces.We infer from these observations that most spermatozoa in vivo initiate their acrosome reactions while they are advancing through the cumulus. When they arrive at the zona surfaces, acrosomal ghosts are generally present on the sperm heads. These ghosts appear to hold sperm heads to zona surfaces as well as to restrict the direction of advancement of sperm head through the zona. In a minority of cases, ghostless spermatozoa reach the zona surfaces. As these spermatozoa appear to be able to penetrate the zona successfully, structures other than the acrosomal ghost (ie, the inner acrosomal membrane and the plasma membrane over the equatorial segment of the acrosome) may also attach to zona surfaces before spermatozoa penetrate into the zona.
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  • 36
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    Gamete Research 8 (1983), S. 325-333 
    ISSN: 0148-7280
    Keywords: cytoplasmic droplet ; spermatozoa ; bovine ; crystalloid ; ultrastructure ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: An elongate crystalloid inclusion has been noted in the cytoplasmic droplet of cauda epididymal bovine spermatozoa. The crystalloid appears to be composed of an aggregate of parallel 10 nm diameter filamentous elements that are associated laterally with one another. It has a regular cross-banding pattern that repeats at 13-15-nm intervals. A purified fraction of detached droplets was prepared by centrifugation of sperm suspensions onto Percoll gradients. The detached droplets also exhibited the crystalline inclusion. The origin and possible functions of this structure are discussed.
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  • 37
    ISSN: 0148-7280
    Keywords: rat ; zona-binding ; fertility ; epididymis ; spermatozoa ; testosterone ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Rat spermatozoa from the proximal caput, the proximal corpus, the middle corpus, and the distal cauda epididymidis were examined for their ability to bind to the zona pellucida after a 1-, 2.5-, or 4.5-h incubation at 34°C with rat eggs in cumulus. Caput spermatozoa did not bind to the zona after 1, 2.5, or 4.5 h of incubation. Corpus spermatozoa did bind to the zona, but the percentage of eggs with bound spermatozoa and number of bound spermatozoa per egg increased with the length of incubation. Cauda spermatozoa bound readily to the zona pellucida, and their zona binding ability did not change with longer incubations. It thus appears that rat spermatozoa gradually acquire the ability to bind to the zona pellucida in the corpus epididymidis.The zona-binding capacity of cold immobilized cauda spermatozoa, defined as the percentage of eggs with bound spermatozoa, increased with the number of spermatozoa incubated and reached a plateau characteristic of the endocrine status of the animal. After castration, zona-binding ability is progressively lost from day 3 until day 10 where it is nil. Testosterone supplementation maintains zona-binding ability to control levels. Similarly, fertilizing ability declines from day 5 after castration until day 10. Testosterone prevents this loss of fertilizing ability. It thus appears that the development of zona-binding ability during epididymal transit is, like the development of fertilizing ability, under androgen regulation.The close correlation between the onset of fertilizing ability and zona-binding ability during maturation, the loss of fertilizing ability and zona-binding ability after castration, and the recovery of both fertilizing ability and zona-binding ability with testosterone treatment suggests that the androgen-dependent development of zona-binding ability is an important component of the acquisition of sperm fertilizing ability during epididymal transit.
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  • 38
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    Gamete Research 9 (1984), S. 131-144 
    ISSN: 0148-7280
    Keywords: spermatozoa ; human ; motility ; activated motility ; hyperactivated motility ; capacitation ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Ten frames/sec microcinematography (“film”), 1 second timed-exposure photomicrography (“photo”), and laser Doppler velocimetry (LDV) were used to analyse the swimming patterns of human spermatozoa after migration (1 h at 37°C) into an overlying layer of either BWW or Menezo's B2 media. The upper layer of medium was carefully removed and further incubated at 37°C for either 4 h (B2) or 5 h (BWW) and the sperm motility analysed again. Five experiments were performed using semen from different donors. Film and photo analyses gave the relative incidence of nonprogressive and progressively motile spermatozoa plus, for the progressive spermatozoa, the velocities of progression (Vp) and amplitudes of lateral head displacement (Ah). LDV gave the percentage of motile spermatozoa and the modal instantaneous velocity (Vm). All postmigration sperm populations showed large significant increases in the percentage of motile spermatozoa, with good survival during incubation. The progressive postmigration spermatozoa generally moved with greater Vp and Ah than in the initial seminal plasma-diluted material; Vm was also increased. There were further increases in both Vp and Ah during incubation, but no change in Vm was detected. While the majority of spermatozoa were progressive, some showed a highly active pattern of movement which resulted in no net forward progression. The possible homology between these spermatozoa and the “hyperactivated” motility of capacitated spermatozoa in other mammalian species is discussed. Apparent discrepancies between the three methods used for motility analysis were seen, the possible causes and significances of which are also discussed.
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  • 39
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    Gamete Research 9 (1984), S. 167-174 
    ISSN: 0148-7280
    Keywords: spermatozoa ; cervical mucus ; human ; motility ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Experiments were conducted to determine some of the biological variables that may affect sperm penetration of human cervical mucus in vitro. Quantitative tests of cervical mucus penetration were carried out to determine the percentage of successful collisons (PSC) between seminal spermatozoa and the semen-mucus interface. Fifteen duplicate comparisons and 15 triplicate comparisons of PSC values were made, each using individual samples of semen and mucus. In most cases the difference between any two comparisons was less than 10%, and there was no correlation between the magnitude of the difference between tests and the absolute value of the PSC. The triplicate comparison showed no correlation between the PSC values and the location of the mucus in the collection catheter (proximal, middle, distal). In 15 experiments the semen was serially diluted with an aliquot of its own plasma to determine the effect of sperm concentration on the PSC. No effects were observed until the sperm concentration fell below 10 × 106 sperm/ml, when the PSC appeared to increase. These results indicate that the tests should be applicable to all but the most severely oligospermic semen samples.
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  • 40
    ISSN: 0148-7280
    Keywords: spermatozoa ; boar ; crater defect ; electron microscopy ; nucleus ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Nuclear vacuoles resembling the “crater defect” described in bull spermatozoa were observed in 14 boars. Both the incidence of the defect and semen quality were monitored with phase contrast microscopy over a three-month period. The percentages of cratered spermatozoa varied widely both among boars and in ejaculates from the same boar taken on different days. The presence of cratered spermatozoa at a level of 5% or more appeared to be associated with low semen quality. The defect was studied with scanning and transmission electron microscopy and was found to consist of nuclear invaginations, about 0.5 μm in diameter, containing some scanty amorphous electron-dense material. In boars showing a high incidence of spermatozoa with crater defects, abnormalities of the acrosome and perforatorium were common.
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    Gamete Research 4 (1981), S. 379-386 
    ISSN: 0148-7280
    Keywords: ferritin ; rabbit ; spermatozoa ; immunolabeling ; ultrastructure ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Ferritin-conjugated goat IgG binds nonspecifically to rabbit sperm. This restricts use of ferritin-labeled goat antiglobulins as indirect labels in rabbit sperm antigen localization. Ferritin-conjugated Protein A does not bind nonspecifically to rabbit sperm and is a satisfactory substitute for indirect (“secondary”) labeling of sperm antigens.
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  • 42
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    Gamete Research 3 (1980), S. 317-322 
    ISSN: 0148-7280
    Keywords: spermatozoa ; cell surface ; lectin receptor ; autoantigen ; Ricinus ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The isolated rabbit sperm plasma membrane autoantigen RSA-1 has been identified as a receptor for the lectin, Ricinus communis I (RCA). Using purified RSA-1 labeled with125 I, the autoantigen was shown to bind to RCA affinity columns and the eluted fraction bound to specific anti-RSA-1 alloantiserum immunoadsorbent columns.
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  • 43
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    Gamete Research 3 (1980), S. 351-367 
    ISSN: 0148-7280
    Keywords: marsupial ; spermatozoa ; nucleus ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Spermatozoa of six species of Australian marsupials have been studied. The nucleus is highly unstable when compared with those of eutherian mammals. When thin films of spermatozoa in buffered saline are air-dried on glass slides, the nucleus disintegrates and flattens, leaving the acrosome, midpiece, and tail intact. This spreading of the nucleus can be inhibited by seminal plasma proteins and by bovine serum albumin, but is potentiated by detergents. The nucleus also decondenses spontaneously in the presence of high concentrations (〉0.25M) of calcium and magnesium salts, leaving the head membranes, acrosome, midpiece, and tail intact. This is inhibited by EDTA. In some species, certain areas of the nucleus appear more resistant t o Ca++/Mg++ treatment, and the initial stages of decondensation are uneven. Ultrastructurally the Ca++/Mg++ dispersed chromatin shows a moderately fine, branching, fibrillar structure, interspersed with dense granules. Treatment with disulphide bond cleaving agents together with detergents results in rapid and complete dispersal of the chromatin and acrosome, and slow digestion of midpiece and tail structures. Treatment with HCl, NaCl, KCl, EDTA, detergents, and sucrose has no effect on nuclear integrity, but treatment with NaOH (0.9-1.0M) results in complete digestion of the whole sperm. These findings are discussed in the light of evolutionary differences between marsupial and eutherian mammals in terms of sperm structure and composition.
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  • 44
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    New York, NY : Wiley-Blackwell
    Gamete Research 6 (1982), S. 81-89 
    ISSN: 0148-7280
    Keywords: adenylate cyclase ; spermatozoa ; calcium ; cyclic AMP ; human ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The adenylate cyclase activity of human ejaculated spermatozoa in broken-cell preparations was investigated. In the presence of 5 mM metal cations and 0.1 mM ATP, the relative enzyme activity with Mn2+, Ca2+, Mg2+, Ba2+ was 1.00, 0.28, 0.22, and 0.03, respectively. Added Ca2+ appeared to activate the enzyme in the presence of Mn2+ or Mg2+. The human sperm adenylate cyclase was stimulated by ∼ 2-fold by free Ca2+ (lmM) in the presence of Mg2+ (5 mM). If the GTP analogue, 5′-guanylyl imidophosphate (Gpp(NH)p) was added to the sperm homogenate in the presence of 200 μM ethylene-glycol-bis (β-aminoethylether) N,N′-tetraacetic acid (EGTA), the adenylate cyclase activity was increased by approximately 25%, but with the addition of 280 μM Ca2+ there was a decrease in enzyme activity. A similar response to low concentrations of Ca2+ was obtained after complementation of the sperm enzyme with the guanine nucleotide regulatory component from human erythrocytes, where the addition of 40 μM Gpp(NH)p, 200 μM EGTA, and Ca2+ (≤ 160 μM) stimulated the sperm enzyme ∼ 3-4-fold, but the further addition of Ca2+ (280 μM, final) neutralized the stimulatory effect. The addition of adenosine, and the nucleotides 5′-AMP and 5′-ADP inhibited the enzyme, whereas guanine and 5′-GMP had no appreciable effect. Human follicular fluid and serum also had little direct effect on the sperm adenylate cyclase. These resuls suggest that Ca2+ might be an important physiological modulator of the human sperm adenylate cyclase.
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  • 45
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    New York, NY : Wiley-Blackwell
    Gamete Research 6 (1982), S. 305-313 
    ISSN: 0148-7280
    Keywords: albumin ; capacitation ; fertilization ; spermatozoa ; zona pellucida ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Serum albumin is an obligatory component of the incubation medium for the fertilization of mouse ova. Normal, untreated bovine serum albumin supports high rates of fertilization of cumulus-free ova both with and without their zonae pellucidae. Heat-treated or trichloroacetic acid-extracted bovine serum albumin is unable to support the fertilization of a majority of zona-intact ova but fertilization of zona-free ova is unimpaired. Spermatozoa incubated in medium containing heated bovine serum albumin fertilize zona-intact ova when 2 mM caffeine is present but the progress of sperm head decondensation is delayed when compared to normal controls. Trichloroacetic acid extracted BSA preferentially and irreversibly inhibits zona penetration by spermatozoa, but this effect is not mediated by an inhibition of spermatozoal motility or zona-binding ability. This effect occurs after only a 10-min preincubation of the spermatozoa in the extracted BSA or when the medium contains only a 10% (v/v) proportion of this albumin. It is estimated that mouse spermatozoa under the conditions used take 2 hr to penetrate the zonae pellucidae of 50% of ova and effect fertilization.
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  • 46
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    Gamete Research 7 (1983), S. 49-61 
    ISSN: 0148-7280
    Keywords: spermatozoa ; isolation ; Centrifugation ; Percoll ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: A procedure using centrifugation in density gradients composed of Percoll was developed for isolation of spermatozoa from mammalian semen. To evaluate the technique, rabbit, human, or bovine semen was layered over continuous Percoll gradients ranging in density from 1.02 to 1.13 gm/ml and centrifuged at 1,500g for 45 min. After centrifugation, the seminal plasma remained above the gradient, whereas the spermatozoa and seminal particles were distributed within the gradient according to their buoyant densities. Unlike most washing techniques, no sperm pellet was formed; instead, the spermatozoa were concentrated into a compact band above the most dense layer of Percoll. The spermatozoa recovered from the gradient were easily resuspended by gentle techniques. Thus, the mechanical stress to the spermatozoa was minimized. Osmotic stress to the spermatozoa was also negligible as the Percoll gradients were isotonic throughout. Spermatozoa obtained by this technique possessed motility equivalent to that of spermatozoa in the unfractionated semen. Sperm suspensions recovered from the gradients contained less than 5% of the nonspermatozoal particles present in the original samples of unfractionated semen. Soluble seminal components were also efficiently removed from the spermatozoa. Thirty billion bovine spermatozoa could be fractionated on a single gradient without loss of effectiveness. Recovery of spermatozoa from these preparative separations averaged 80%. These results demonstrated that Percoll was a superior medium for efficient density gradient isolation of motile spermatozoa free of contamination by other seminal constituents.
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  • 47
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    Gamete Research 7 (1983), S. 199-214 
    ISSN: 0148-7280
    Keywords: ultrastructure ; spermatozoa ; nucleus ; Bivalvia ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Sperm ultrastructure and spermiogenesis of the three bivalve species Musculus discors, Nucula sulcata, and Dreissena polymorpha have been studied. During spermatid differentiation in Musculus discors and Nucula sulcata the nucleus attains an elongated rod-like shape. The spermatozoon from Nucula sulcata was found to have a cup-shaped acrosome and five mitochondria surrounding two centrioles in the middle piece. The spermatozoa from Musculus discors has a long complex acrosome. From the distal centriole striated processes extend and attach to the plasma membrane. The spermatozoon of the fresh water species Dreissena polymorpha agrees in all main features with those of other invertebrate groups with external fertilization. It is thus of the primitive type with barrel-shaped nucleus and four to five mitochondria1 spheres in the middle piece. The acrosome is a prominant, complex structure at the apex of the mature spermatozoon.A comparison of sperm ultrastructure among bivalves indicates that there is a certain correlation between the evolution of the elongated sperm nucleus and large, yolk-rich eggs. In species with an elongated sperm nucleus the increased egg size has often led to a lecithotrophic or direct development. The elongated nucleus is a slight modification of the primitive type. There is a great variation in acrosome structure among bivalve spermatozoa, reflecting diverging functional demands at fertilization of the eggs.
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  • 48
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    Gamete Research 7 (1983), S. 347-350 
    ISSN: 0148-7280
    Keywords: Taurine-related compounds ; taurine antagonists ; taurine uptake inhibitors ; fertilization in vitro ; hamster ; spermatozoa ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Several taurine-related compounds, taurine antagonists and taurine uptake inhibitors were tested for their effect on hamster sperm motility in vitro. Hypotaurine was approximately three times more effective than taurine. N-methyltaurine and taurocyamine were less effective. Inactive taurine-related compounds were not effective blockers of taurine's spermtimulating activity. However, 1-(4-nitrophenyl)-2-dimethylaminomethyl-l-propenone, a taurine uptake inhibitor, completely suppressed sperm motility at a molar concentration equal to, or less than, that of the taurine added to the incubation medium and also suppressed the motility-sustaining action of the cumulus oophorus.
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  • 49
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    Gamete Research 8 (1983), S. 309-323 
    ISSN: 0148-7280
    Keywords: spermatozoa ; Nematoda ; evolution ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The main features of the Nematode sperm cell are the absence of a flagellum and of an acrosome. Transition forms have never been described, as in other animal phyla also reaching the aflagellate condition, like Platyhelminths and Arthropods. The absence of the flagellum must be considered as a definitive acquisition in the group. In addition, centrioles have been demonstrated to be lacking in most cases. The absence of the acrosome is the second general feature of the Nematode sperm cell. Among other features, more or less common to the Nematodes, the most important and general is the presence in the cell periphery of spheroidal membranous vesicles, originated from the Golgi complex but not involved in fertilization or in the production of ascaridin granules. These are absent only in the Ascarid Aspiculuris and the Dorylaimiid Xiphinema, both kinds of sperm having a peculiar shape. These granules are possibly involved in cell motility. Some Nematode sperm have proteinaceous crystalline inclusions originated from the rough endoplasmic reticulum, called ascaridin granules, the role of which remains obscure. A third important feature is the absence of a nuclear envelope, characterizing all described Nematode spermatozoa, the only exception being the Enoplid Mesacanthion, which seems to be for this reason the most primitive model in the group. Other features are the reduced number, or total absence of, the chondriome, an amoeboid movement not owing to an actomyosin system and a dense halo of 10-nm filaments surrounding the perinuclear cytoplasm.In this apparently homogeneous picture, three main evolutionary steps can be recognized. The first one, represented by the primitive Enoploid Mesacanthion, is that of a sperm conserving the nuclear envelope, surrounded by a few mitochondria and many membranous vesicles. The second, the most typical of the group, present in high Enoplida, and in Rhabditida, Strongylida, Ascarida, Spimrida, Trichinellida, is that of roundish, amoeboid spermatozoa devoid of a nuclear envelope but containing mitochondria, membranous vesicles, filaments, microtubules, sometimes centrioles, and sometimes ascaridin granules. The third step is apparently a simplification of the second; in fact, in Tylenchida and Dorylaimiida, the sperm is devoid of membranous vesicles, while in Mononchida and Dioctophymatida it is devoid of mitochondria. Aspiculuris, also devoid of membranous vesicles and having a big mitochondrial derivative, can be assigned to the same level. Nematode sperm evolution does not seem therefore to be a progressive acquisition of new characters, but rather a radiation from an already perfect model of some further simplifications occurring in parallel in most of the orders.
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