摘要:

AbstractPig oocytes obtained from slaughterhouse material and rat oocytes obtained from PMSG‐treated immature females were incubated as isolated oocytes or injected into explanted pig follicles (5–8 mm). Free oocytes of both species, with or without their cumulus investment or gonadotropins during culture, matured at high rates after 30 hr or 9–10 hr of culture, respectively. Gonadotropic stimulation was necessary for maturation of both the native and injected cumulus‐intact pig oocytes in follicle culture. Cumulus‐free pig oocytes injected into follicle failed to mature in response to gonadotropic stimulation, suggesting an inability to perceive or respond to stimulation. Injected rat oocytes, however, matured irrespective of cumulus investment or gonadotropic stimulation. Their maturation was delayed and reduced at 9 hr. These results in the rat suggest that the pig follicular environment is incapable of regulating rat oocyte maturation but rather presents a permissive or supportive environment for their maturation. The explanted surrogate follicles from the pig or other species may provide a useful model for the study of oocyte‐follicle interactions in oocyte maturation within or betw

ISSN:0148-7280    

DOI:10.1002/mrd.1120110202

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractHamster and mouse capacitated spermatozoa were interacted in vitro with hamster and mouse eggs in homologous and heterologous combinations. Also, fertilized and trypsin treated unfertilized hamster eggs, and unfertilized rat eggs were made to interact with capacitated hamster spermatozoa. The surface of the zona pellucida was then examined with the scanning electron microscope. It was found that sperm attachment, followed by sperm binding and penetration through the zona pellucida, was observed only when homologous gamete combinations were used. Binding of the spermatozoa to the zona was evidenced by the lytic effect of the acrosomal enzymes on the zona substance. When fertilized eggs and trypsin‐treated unfertilized hamster eggs were mixed with capacitated hamster spermatozoa as well as in the heterologous gamete combinations, we found that the spermatozoa were able to establish attachment but not binding. Under these conditions the outer surface of the zona pellucida was never found to have penetration tracks made by the spermatozoa. Failure of heterologous spermatozoa to cross the foreign zona pellucida is believed to be associated with the inability of the foreign spermatozoa to establish binding and to the inability of their acrosomal enzymes to digest the zona. A similar mechanism is believed to work in zona‐reacted and in trypsin‐treated hamster eggs inseminated in vitro with homologous sperma

ISSN:0148-7280    

DOI:10.1002/mrd.1120110203

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractEstradiol 17‐β (E2) was found to either inhibit or synergize Na‐insulin (Ins)‐induced meiotic maturation of Rana oocytes. Inhibition of Ins activity occurred in the presence of the follicular investments of the oocyte; synergism with Ins occurred in oocytes denuded of the follicle wall. Similarly, co‐incubation of E2 with frog pituitary homogenate (FPH) or pregnenolone (Pe) significantly decreased meiotic reinitiation as determined by germinal vesicle dissolution (GVD) in follicle‐enclosed oocytes. By contrast, E2 had no consistently significant effect on progesterone (P)‐induced meiosis in follicle‐enclosed oocytes. Furthermore, E2 had no significant effect, either inhibitory or synergistic, on Pe‐ or P‐induced GVD of denuded oocytes. Thus, of the meiotogens tested (Ins, P, Pe, FPH), all but P were consistently inhibited by E2 in the presence of the follicle wall. Na‐insulin was the only meiotogen tested (Ins, P, Pe) which was potentiated by E2 in denuded oocytes, However, when E2 and Ins were spatially separated on the surface of individual intact follicles, the result was synergism of Ins‐induced GVD rather than inhibition. These results suggest that Ins acts to induce GVD in the denuded oocyte through a mechanism distinct from that used by P (ie, Ins mechanism allows E2 synergism while the P mechanism does not). The E2 inhibitory effect on Ins‐induced GVD appears to be dependent upon simultaneous exposure of follicle wall tissue to mixtures of E2 and Ins. The synergistic effect of E2 on Ins‐induced GVD is dependent upon the simultaneous exposure of the oocyte surface to Ins and E2, either as a homogenous mixture in the case of denuded oocytes or as single substances at independent sites, for

ISSN:0148-7280    

DOI:10.1002/mrd.1120110204

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractAntiserum to purified boar spermatozoan outer acrosomal membrane (OAM) was raised in rabbits and adsorbed with boar liver and serum glutaraldehyde cross‐linked immunoadsorbents. The IgG fraction of the antiserum was purified by (NH4)2SO4precipitation followed by ion‐exchange chromatography. Indirect immunofluorescence showed bright fluorescent staining of the acrosomal cap of boar spermatozoa and to a lesser extent of the acrosomes of bull and goat spermatozoa after incubation with anti‐OAM‐IgG. Immuno‐electron microscopy further confirmed the specificity of the antibody for the OAM. Preincubation of the anti‐OAM‐IgG with isolated OAM, completely abolished its reactivity. When tested by ELISA, anti‐OAM‐IgG reacted with boar, bull, goat, and human spermatozoa; however, its binding activity to boar spermatozoa was significantly greater as compared to spermatozoa from the other species tested.In an effort to identify OAM antigens recognized by this antiserum, the isolated boar OAM was labeled either with3H or with125I and solubilized by mild detergent treatment. The extracted components were immunoprecipitated with anti‐OAM‐IgG and protein A‐bearing S. aureus and the thus isolated antigens were analysed on SDS‐PAGE. The results suggest that anti‐OAM‐IgG recognized one high molecular3H‐labeled glycoprotein (270 kd), and four125I‐labeled polypeptides of lower

ISSN:0148-7280    

DOI:10.1002/mrd.1120110205

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractWhen the spermatozoon of M glacialis contacts the mature oocyte jelly it adheres to it. Following this, there is a slight tumefaction of the acrosome, which is followed by the disruption of the apical acrosomal vesicle and cytoplasmic membranes. Acrosomal vesicle contents are liberated and spread along the outer surface of the oocyte jelly. Meanwhile, the acrosomal process begins to extend, penetrates all the jelly extension, then the vitelline layer, and finally contacts the cytoplasmic egg membrane. Nevertheless, the sperm cell continues lying at the outer border of the jelly. From the beginning of the acrosome reaction the dense and finely fibrillar subacrosomal material is connected, by some expansions, to the basal acrosomal vesicle membrane. Both nuclear and mitochondrial diameters have diminished.

ISSN:0148-7280    

DOI:10.1002/mrd.1120110206

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractAn objective method of estimating the motility of fowl and turkey spermatozoa, depending on their rheotactic and light‐scattering properties, has been developed. From a 1‐ to 2‐minute recorder trace of the optical density of diluted semen before and after stopping its passage through a flow cuvette, three independent constants may be simply and graphically determined. These are: ODm, the maximum optical density of semen flowing through the cuvette, shown to be dependent on the concentration of spermatozoa; % (ΔOD)m, the maximal change of optical density following cessation of flow, which has been correlated with the percentage of motile spermatozoa in the sample; and t½, the time taken for the change of optical density to reach % (ΔOD)m. This latter parameter has been correlated with forward motility of both fowl and turkey spe

ISSN:0148-7280    

DOI:10.1002/mrd.1120110207

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractThe nature and control of changes in surface carbohydrates in capacitating hamster spermatozoa were analysed by using five inhibitors of glycoprotein biosynthesis in an in vitro fertilization system. Epididymal spermatozoa were treated with amphomycin, bacitracin, tunicamycin, 2‐deoxyglucose, and 2‐deoxy‐2‐fluoro‐D‐glucose either during the entire period of capacitation or briefly at the end of capacitation before exposing to Con A‐coated agarose beads or hamster eggs with or without their zonae pellucidae. Untreated 4½‐5‐hr spermatozoa exhibited nearly 100% fertilization and became bound to Con A‐agarose beads mainly along the length of their flagellae, resulting in the formation of clumps on the beads. In the presence of inhibitors of glycosylation, spermatozoa did not bind to Con A‐agarose beads or zona‐intact oocytes and they did not fuse with the zona‐free oocytes. Sperm‐zona binding was also inhibited by UDP‐galactose and UDP‐N‐acetylglucosamine, but not by UDP‐glucose. Sperm motility was not damaged by these inhibitors, and zona‐intact and zona‐free oocytes pretreated with these inhibitors underwent normal fertilization with untreated spermatozoa. These results further strengthen the view that glycoproteins on the sperm surface may be required during different stages of f

ISSN:0148-7280    

DOI:10.1002/mrd.1120110208

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

ISSN:0148-7280    

DOI:10.1002/mrd.1120110209

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

ISSN:0148-7280    

DOI:10.1002/mrd.1120110201

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY