摘要:

AbstractThe process whereby hamster oviductal fimbria transport ova to the ampulla was investigated in vitro and in vivo with the intent of determining whether cumulus‐free ova were transported and resolving some of the parameters involved in cumulus‐isolated from ovaries could not be picked up until 16–17 h before it would be ovulated. This was apparently related to the time at which the cumulus matrix begins to expand. The fimbria were not species‐specific, as they readily picked up rat, mouse, and rabbit ovulated cumul, but they were partially tissue‐specific as they would only pick up tissues such as the vitreous humor and loose connective tissue, which contain considerable extracellular glycosaminoglycan. Interaction of cumulus and fimbria could be prevented b treating either structure with polycatinic macromolecules such as poly‐l‐lysine, cationic ferritin, and protamine. Treatment of fimbria with proteolytic enzymes or hyaluronidase did not prevent pickup, but neuraminidase did. The only “artificial cumulus” the fimbria would pick up was chicken egg‐white. Cumulus‐free ova were not picked up in vitro, but part of them placed into the ovarian bursa were transported to the ampulla in vivo. Coating the ova with chicken egg‐white allowed their pickup in vitro, but had little effect on the success of transport of ova transplanted into the ovarian bursa in vivo. The transport of ova from the ovarian bursa to the oviductal ampulla is apparently a rather complex process involving interaction of some component of the cilia surfaces with the cumulus as well as other factors not necessarily rela

ISSN:0148-7280    

DOI:10.1002/mrd.1120080102

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

年代:1983

数据来源: WILEY

摘要:

AbstractRabbit‐ejaculated spermatozoa were incubated in a chemically defined medium containing comercially available glycosaminoglycans (GAGs) at concentrations ranging from 0.1 to 100 μg/ml. Sperm were stained and examined for the degree of acrosome reaction and viability after 9 h of incubation. There were significant dose and treatment effects of the induction of the acrosome reaction. Viability did not differ significantly betweendoses or treatment. Heparin enhanced the acrosome reaction between concentrations of 0.1 to 1.0 μg/ml, whereas higher levels depressed the percentage of sperm undergoing the acrosome reaction. Seminal plasma added to sperm cultures depressed the stimulatory effect of GAGs. Treatment of chondroitin‐4‐sulfate with chondro‐4‐sulfatase prohibited the stimulatory effect. It is concluded that GAGs, components of the female reproductive tract, may promote the acrosome reaction so that successful fertilizatio

ISSN:0148-7280    

DOI:10.1002/mrd.1120080103

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

年代:1983

数据来源: WILEY

摘要:

AbstractPure ram protamine isolated from epididymal spermatozoa was used to raise antisera in castrated rabbits. The antibodies were visualized in the electron microscope using the method of Moriarty and Halmi [1972] with either peroxidase or coupling with colloidal gold. The gold gave better contrast but lower afinity than the peroxidase method. With the use of fixation according to Thiery and Rambourg [1976]and thick sections treated with hydrogen peroxide, it was possible to detect the protamine in the cytoplasm near the flagellum and the chromatoid body of step 12 spermatids. It was concluded that protamine enters the nucleus and concentrates at that step in the ram.

ISSN:0148-7280    

DOI:10.1002/mrd.1120080104

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

年代:1983

数据来源: WILEY

摘要:

AbstractOn the basis of structural observations bovine oocytes were grouped into four successive classed: 0, those before the luteinizing hormone (LH) surge; 1, those up to 8 h following the LH peak level; 2, those between 8 and 19 h after the LH peak level; and 3, those between 19 h after the LH peak level and ovulation.Oocytes in class 0 had mitochondria located in a generally peripheral position. Interior to the mitochondria were elements of rough endoplasmic reticulum (RER) and numerous membrane‐bound vesicles which bore ribosome‐like particles on their outer surface. The first visible changesater the LH peak level as seen in class 1 were the formation of the periviteline space with loss of contact between the cumulus cells and the oocyte, and ruffing of the nuclear envelope. These changes were followed b the resumption of meiosis as defined by germinal‐vesicle breakdown (GVBD), the disappearance of RER, and the formation fo clusters of mitochondria in association with lipid droplets and elementrs of smooth endolasmic reticulum (SER).The period between 8 and 19 h following LH peak level (class 2) was characterized by intensive clustering of mitochoncria in association with lipid droplets and elements of SER, conversion of lipid, fusion of vesicles, and the appearance of ribosomes in the cytoplasm. During the final stage (class 3), the polar body was extruded, the mitochondria dispersed, and the majority of the organelles became located toward the center of the cell. The relatively organelle‐free cortical region contained cortical granules immediately adjacent to the plasma membrane together with aggregates of tubular SER. The structural changes are discussed in the context of follicular steroidogenesis and oocyte developmental com

ISSN:0148-7280    

DOI:10.1002/mrd.1120080105

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

年代:1983

数据来源: WILEY

摘要:

AbstractFerritin‐labeled antibody to calmodulin was localized in flagella of guinea pig sperm. Ferritin granules were present on the surface of the medial portion of the coarse fibers, and in the matrix immediately surrounding this segment of the fibers. The results demonstrate that calmodulin is confined to regions close to the tubulin‐dynein systems os the axoneme. A calcium‐dependent ATPase was localized in the same region by trapping the reaction product with cadmium. The presence together of calmodulin and the Ca2+‐ATPase close to the axonemal complex suggests that they function to control the concentration of Ca2+, which in turn may regulate the action of the dynein ATPase, and sperm motility. The remainder of the coarse fiber surface also contains specialized material as evidenced by intense staining with ethanolic phosphotungstic acid. These data suggest that the role of the coarse fibers is complex and may not be solely str

ISSN:0148-7280    

DOI:10.1002/mrd.1120080106

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

年代:1983

数据来源: WILEY

摘要:

AbstractFollicular oocytes collected prior to the expected time of the LH surge from PMSG‐treated immature rats were incubated cummulus‐intact (with or without LH) or cumulus‐free (CF). Oocytes were incubated in the presence or absence of lysophosphatidlylserine (LS), a naturally occurring membrane phospholipid that has been previously shown to block sperm‐related membrane fusion events. Fusion events occurring during oocyte maturation that might be affected by LS include maintenance of the intact germinal vesicle (GVI) and prevention of GV breakdown (GVBD) and first polar body formation (PBI). LS had only a slight effect upon GVI. The incidence of GVI was significantly increased in only one of the three oocyte culture conditions employed (CF). Exposure to LS from the outset of collection and washing did not increase the incidence of GVI, indicating the lack of effect by LS was not owing to the passage of a sensitive period during oocyte collection. In contrast, LS was not owing to the passage of a sensitive period during oocyte colection. In contrast, LS almost completely abolished PBI in all oocyte culture conditions at 100 μ in PBI and those sperm‐related fusion processes previously found to be sensitive to LS. Finally, LS or similar agents may be responsible for the block to maturation (often at anaphase I) and even the retarded cleavage observed in vitro during oocyte maturation or embryo culture in so

ISSN:0148-7280    

DOI:10.1002/mrd.1120080107

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

年代:1983

数据来源: WILEY

摘要:

AbstractStudies examining cytoplasmic and sperm nuclear transformations in sea urchin (Arbacia punctulata) eggs inseminated at different periods after ammonia activation have been caried out at the light‐ and electron‐microscopic levels of observation. Arbaca eggs treated with ammonia‐seawater demonstrated chromosome condensation after DNA synthesis and underwent a chromosome cycle similar to that described for Lytechinus [Mazia, 1947]. Cortical granule reaction, fertilization cone formation, and sperm aster development in eggs fertilized at 20 (interphase), 50 (prometaphase), and 180 (interphase) min after ammonia activation were structurally simialr to processes in untreated zygotes. Cyclical changes in the formation of fertilization cones and sperm asters, as reported for eggs fertilized after activation by agents that induce a cortical granule reaction, were not observed. Although sperm nuclear transformations were prolonged (14 vs 18 min), male pronuclei that developed in eggs fertilized 20 min after ammonia activation were morphologically similar to those observed in fertilized, untreated ova and incorporated3H‐thymidine. Sperm incorporated into eggs at 50 min after ammonia activation underwent nuclear envelope breakdown and chromatin despersion; however,3H‐thymidine incorporation was not observed, and male pronuclei rarely developed (less than 5% of all specimens examined). Subsequent to dispersion, the paternal chromatin condensed into chromosomes which were associated with an aster. These results demonstrate that although ammonia‐activated eggs inseminated at interphase or prometaphase undergo similar cytoplasmic alterations, sperm nuclear transformations vary with the chromosome cycle

ISSN:0148-7280    

DOI:10.1002/mrd.1120080108

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

年代:1983

数据来源: WILEY

摘要:

AbstractThis study examined the possible role of steriods in meiotic maturation of preovulatory oocytes. Follicles were isolated from PMSG‐treated immature rats and incubated with or withour LH in the presence of one of four inhibitors of steroidogenesis. The inhibitors employed had different sites of attack in the steriodogenic pathway and were aminoglutethimide, cyanoketone, SU 10603 (17β‐hydroxylase inhibitor), and 4‐OH‐androstenedione (aromatase inhibitor). As predicted, the inhibitors drastically altered the pattern of steroid production. None of the inhibitors, however, changed the proportion of oocytes resuming or completing meiosis in response to LH, and there was also no effect of the inhibitors on the oocytes in the absence of LH. It was concluded that steriods are not required for preovulatory nuclear maturation of oocytes in

ISSN:0148-7280    

DOI:10.1002/mrd.1120080109

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

年代:1983

数据来源: WILEY

摘要:

AbstractThis study was designed to investigate the mechanism of the subfertility produced when male mice are exposed to high pressure [Baden et al, 1982]. In the first series of experiments, male BALB/c mice were exposed to 50 ATA helium pressure intermittently throughout spermatogenesis (5 weeks). Control mice were exposed to 1 ATA air under identical conditions for an equivalent period. Immediately after exposure half the mice in each group were sacrificed, the remainder being sacrificed 14 days later. Testes were weighed and prepared for histological examination, and spermatozoa were examined for motility and abnormalities. More testes in the pressure group had disorganised seminiferous epithelia and weighed less than the control group; in addition the motility of sperm was also reduced immediately after pressurisation.In the second series, male mice were exposed to 50 ATA pressure, or 1 ATA air intermittently for only 1 week to assess whether this exposure, for a period sufficient only to affect epididymal sperm, had any effect on functional fertility. The males were subsequently mated with untreated females; no difference was seen between the groups for pregnancy rate, preimplantation loss, or fetal survival.These data support the idea that the changes in spermatogenesis causing subfertility in mice are fairly subtle, but are consistent with the premature release of spermatids from seminiferous epithelium. Epididymal sperm remained functionally unaffected by exposure to high pressure.

ISSN:0148-7280    

DOI:10.1002/mrd.1120080110

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

年代:1983

数据来源: WILEY

ISSN:0148-7280    

DOI:10.1002/mrd.1120080111

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

年代:1983

数据来源: WILEY