摘要:

AbstractZona‐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

ISSN:0148-7280    

DOI:10.1002/mrd.1120050302

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

年代:1982

数据来源: WILEY

摘要:

AbstractIntercellular coupling between cumulus cells and oocytes persists after oocyte meiotic maturation has been initiated. The experiments described here focus on the relationship between oocyte‐cumulus cell intercellular coupling during maturation and the subsequent embryonic development of spontaneous mouse parthenotes. Several lines of evidence suggest that this coupling during oocyte maturation is required for the acquisition of the capacity for spontaneous mouse parthenotes to develop embryologically. First, the period of time that LT/Sv oocytes remained coupled to cumulus cells during oocyte maturation in vivo corresponded to that required for the acquisition of the capacity for parthenogenetic embryonic development. Second, the longer that cumulus cells were present during Fpontaneous oocyte maturation in vitro, the higher was the percentageofova undergoing subsequent parthenogenetic development. Third, cumulus cell‐free oocytes cocultured with cumulus cell‐enclosed oocytes during the maturation period in vitro did not develop embryologically. Fourth, intercellular coupling between cumulus cells and oocytes persisted throughout the oocyte maturation period in vitro. Fifth, incubation of oocyte‐cumulus cell complexes in medium containing follicle‐stimulating hormone (FSH) promoted uncoupling and decreased the percentage of ova undergoing parthenogenetic development. Thus, cell‐to‐cell communication, mediated via the intercellular coupling pathway between cumulus cells and oocytes, plays an important role during oocyte maturation and relates to subsequent preimplantatio

ISSN:0148-7280    

DOI:10.1002/mrd.1120050303

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

年代:1982

数据来源: WILEY

摘要:

AbstractLittle is known about the timing of the mammalian sperm acrosome reaction during fertilization in vivo. To study this problem, female hamsters were inseminated at about the time of ovulation, and the contents of the ampullary regions of their oviducts were subsequently examined at various intervals. No living spermatozoa were recovered from ampullae earlier than 4 hr after insemination. The first appearance of living spermatozoa coincided closely with the first appearance of fertilized eggs in the same oviduct. The total numbers of living spermatozoa did not start to exceed the number of eggs in the same ampulla, until after 50% or more of the eggs had been fertilized. Hamster spermatozoa are highly efficient at making contact with eggs, and the fertilizing spermatozoon probably spends no more than 2½ –5½ min in penetrating the cumulus oophorus. Spermatozoa that enter the ampulla appear to be ready to undergo the acrosome reaction, and complete it while they are passing through the cumulus or shortly before, or after, contacting the surface of the zona pelluc

ISSN:0148-7280    

DOI:10.1002/mrd.1120050304

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

年代:1982

数据来源: WILEY

摘要:

AbstractThe effects of luteinizing hormone (NIH‐bovine LH) and progesterone on maturation in vitro of oocyte‐cumulus complexes from adult proestrous rats were studied by comparing proportions of oocytes showing germinal vesicle breakdown, mucification of the cumulus oophorus, and fertilizability. Addition of either or both of the hormones to the medium in concentrations between 1.25 and 10 μg/ml during maturation had no discernible effect on germinal vesicle breakdown or on fertilization. Mucification was stimulated by LH and even more by LH plus progesterone. It was concluded that maturation in vivo is the result of concerted action of the two hormones. However, addition of LH + progesterone had no effect on the fertilizability of these oocytes. We attribute this to a relative insensitivity of the system for fertilization in vitro to subtle changes in the oo

ISSN:0148-7280    

DOI:10.1002/mrd.1120050305

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

年代:1982

数据来源: WILEY

摘要:

AbstractThe 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.

ISSN:0148-7280    

DOI:10.1002/mrd.1120050306

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

年代:1982

数据来源: WILEY

摘要:

AbstractA double antibody radioimmunoassay technique is described for the measurement of anti‐zona antibodies in the peripheral plasma of marmosets actively immunized against intact cow zonae pellucidae. The method has been shown to be a reliable, repeatable indicator of antibody titer, enabling direct comparison of the response obtained between marmosets. This is the first report of a procedure describing the active immunization of a primate against zona antigens, and the first time a radioimmunoassay technique has been used to monitor profiles of anti‐cow zona antibody production following active immunization. The method should prove to be a useful tool in the evaluation of zona antigens as agents for immunocontracept

ISSN:0148-7280    

DOI:10.1002/mrd.1120050307

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

年代:1982

数据来源: WILEY

摘要:

AbstractTo gain insight into the role of protein phosphorylation during early mammalian development, seven mouse preimplantation stages were metabolically labeled with radioactive orthophosphate and the radiolabeled proteins identified using gel electrophoresis and autoradiography. The results obtained indicate that there are marked differences in protein phosphorylation patterns between the zygote and two‐cell stage and between the morula and blastocyst stage. In addition, there is a compaction‐specific change in the phosphorylation profile of three components of Mr 37,000. This compaction‐specific change takes place during compaction in the eight‐cell embryo; thus, it is the first biochemical change specifically correlated to this important event of early deve

ISSN:0148-7280    

DOI:10.1002/mrd.1120050308

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

年代:1982

数据来源: WILEY

摘要:

AbstractThe presence of a protease has been demonstrated in sperm of the solitary ascidian, Halocynthia roretzi, by using t‐butyloxycarbonyl‐L‐Val‐L‐Pro‐L‐Arg‐4‐methylcoumaryl‐7‐amide (Boc‐Val‐Pro‐Arg‐MCA) and other arginyl or lysyl MCA derivatives as substrates. Several properties of the enzyme were investigated in a crude extract. The activity had a pH optimum near 8.0 and was enhanced by the addition of CaCl2. The Km value of 87μM was determined for Boc‐Val‐Pro‐Arg‐MCA under the optimal conditions. An apparent molecular weight was estimated to be 35,000 by gel filtration. The enzyme was inhibited with diisopropyl fluorophosphate, leupeptin, antipain, p‐aminobenzamidine, Val‐Pro‐Arg‐CH2Cl, and soybean trypsin inhibitor, but scarcely inhibited with chymostatin, elastatinal, p‐chloromercuribenzoic acid, tosyl‐Lys‐CH2Cl, and tosyl‐Phe‐CH2Cl. Boc‐Val‐Pro‐Arg‐MCA, the most susceptible of the substrates examined, showed the most effective inhibition against fertilization of ascidian eggs.Thus, this enzyme in ascidian sperm extract has features closely similar to mammalian acrosin [EC 3.4.21.10], and we conclude t

ISSN:0148-7280    

DOI:10.1002/mrd.1120050309

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

年代:1982

数据来源: WILEY

摘要:

AbstractGlycoprotein synthesis in pachytene spermatocytes and round spermatids, isolated from rat testes, was studied by analysis of the incorporation of (3H)‐fucose. The isolated germ cells were capable of incorporating (3H)‐fucose into cell‐bound, acid‐precipitable components for an incubation period of at least 23 hours (at 32°C). In young spermatids, engaged in the formation of the acrosome, (3H)‐fucose was incorporated into more than 16 different glycoproteins within the molecular weight range of 20.000–100,000. A qualitatively similar set of glycoproteins was found to be labeled in spermatocytes. Radioautography showed that after 4 hr most of the incorporated radioactivity was present at one pole in the perinuclear zone of spermatocytes and spermatids, which could reflect incorporation of fucose in the Golgi apparatus. The newly fucosylated glycoproteins were associated with a particulate subcellular fraction (membrane fraction). Trypsin treatment of whole cells after 25 hours of incubation with (3H)‐fucose, however, did not cause significant lysis of tritiated glycoproteins.From the results it was concluded that the majority of the newly fucosylated glycoproteins in spermatocytes and spermatids remained associated with an intracellular membrane system, presumably the Golgi apparatus and the vesicles that arise from this structure, to be deposited subsequently in proacrosomic granules and the acrosome. The results also suggest that initiation of the synthesis of spermatidal glycoproteins occurs during the prophase of meiosis in

ISSN:0148-7280    

DOI:10.1002/mrd.1120050310

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

年代:1982

数据来源: WILEY

摘要:

AbstractThe spermatozoa of the neotropical hystricomorph rodent Ctenomys maulinus have been examined cytochemically and under the transmission electron microscope. The head is flattened dorsoventrally. At the caudal end of the head there is a process oriented parallel to the tail. This process corresponds to a cylindrical extension of the nucleus, which constitutes a unique feature among mammals.

ISSN:0148-7280    

DOI:10.1002/mrd.1120050311

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

年代:1982

数据来源: WILEY