The Effect of Uterine Environment during Peri-implantation Period on theUltrastructure of Zona Pellucida in Mouse Oocytes and Embryos / 대한불임학회지

In the studies on the hatching mechanisms in mammals, many investigators focused on the embryonic intrinsic factor(s) in in vitro culture, but the uterine environment as the extrinsic factor(s) is thought to play an important role in hatching mechanism. Therefore, to evaluate the effect of uterine environment on the hatching event in vivo, the immature(GV) and ovulated(MII) oocytes, and the late 2-cell embryos of mouse were transferred to pseudopregnant foster mother's uterus during peri-implantation period. So it was verified whether there would happen hatching by only uterine environment independently on embryonic stage. The ultrastructural changes of the zona surface of transferred group were compared with those of in vivo and vitro group by SEM. 36 hrs after transfer, the immature and ovulated oocytes almost degenerated, and the late 2-cell embryos developed to various embryonic stages. However, the embryos which didn't develop to blastula stage did not hatch. The ultrastructural network of ZP in transferred group seemed to be smoothed uniformly, which was different from in vitro group. In conclusion, it is suggested that the uterine environment during peri-implantation period enhances the embryo hatching by provoking the structural change of ZP.

Expression of Luteinizing Hormone(LH) Gene in Human Uterus / 대한불임학회지

OBJECTIVES: Recent studies, including our own, demonstrated that the novel expression of LH gene in rat gonads and uterus, indicating that the local production and action of the LH-like molecule. In the present study, we investigated whether human uterus also expresses the LH gene. DESIGN: Reverse transcription-polymerase chain reaction (RT-PCR) amplified the cDNA fragments coding LHbeta polypeptide from human endometrium but not from myometrium. Presence of the transcripts for the alpha-subunit in human endometrium was also confirmed by RT-PCR. RESULTS: Transcripts for LHbeta subunit were detected in endometrial samples from women with endometriosis. The gene for LH/hCG receptor was expressed in both endometrium and myometrium, showing good agreement with previous studies. Increased level of LHbeta transcript was determined in the endometrium from follicular phase compared to that from luteal phase. CONCLUSION: Taken together, our findings demonstrated that 1) the gense for LH subunits and LH/hCG receptor are expressed in human uterus, 2) the uterine LH expression was changed during menstrual cycle, suggesting that the uterine LH may play a local role in the control of uterine physiology and function(s).

Expression of Luteinizing Hormone (LH) and Its Receptor Gene in Uterus from Cycling Rats / 대한불임학회지

OBJECTIVE: There is increasing evidence for the expression of rat LH gene in several extrapituitary sites including testis and ovary. We also have demonstrated that the local LH expression in the rat epididymis and uterus, the major accessory sex organs in male and female reproductive system, respectively. DESIGN: The present study was undertaken to elucidate whether the gene for LH receptor is expressed in rat uterus and whether the expression of uterine LH and its receptor are differentially regulated during estrous cycle. Presence of the transcripts for rat LH receptor in the rat uterine tissue were confirmed by touchdown reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: In LHbeta semi-quantitative RT-PCR, the highest expression level was shown in estrus stage. The level of LH receptor transcripts was also fluctuated during estrous cycle. In ovariectomized rats (OVX + Oil), the expressions of both uterine LH and LH-R were markedly reduced when compared to those from normal rats. Supplement with estradiol 17beta to the ovariectomized rats (OVX + E2) restored the expression levels of LH and its receptor to the levels in uteri from normal rats. CONCLUSION: Our findings indicated that 1) LH and its receptor gene are expressed in the rat uterus from cycling rats, 2) the expression of uterine LH and its receptor is mainly, if not all, under the control of ovarian sex steroid(s). These results suggested that the uterine LH may act as a local regulator with auto and/or paracrine manner, though the posibility that the pituitary LH may act directly on the regulation of uterine functions could not be discarded.

Effects of Follicle Cells on the Chymotrypsin Resistance of Mouse Oocytes / 대한불임학회지

OBJECTIVE: Mammalian follicle cells are the most important somatic cells which help oocytes grow, mature and ovulate and thus are believed to provide oocytes with various functional and structural components. In the present study we have examined whether cumulus or granulosa cells might play a role in establishing the plasma membrane structure of mouse oocytes during meiotic maturation. DESIGN: In particular the differential resistances of mouse oocytes against chymotrypsin treatment were examined following culture with or without cumulus or granulosa cells, or in these cell-conditioned media. RESULTS: When mouse denuded oocytes, freed from their surrounding cumulus cells, were cultured in vitro for 17~18 hr and then treated with 1% chymotrypsin, half of the oocytes underwent degeneration within 37.5 min (t50=37.5+/-7.5 min) after the treatment. In contrast cumulus-enclosed oocytes showed t50=207.0. Similarly, when oocytes were co-cultured with cumulus cells which were not associated with the oocytes but present in the same medium, the t50 of co-cultured oocytes was 177.5+/-13.1 min. Furthermore, when oocytes were cultured in the cumulus cell-conditioned medium, t50 of these oocytes was 190.0+/-10.8 min whereas t50 of the oocytes cultured in M16 alone was 25.5+/-2.9 min. Granulosa cell-conditioned medium also increased the resistance of oocytes against chymotrypsin treatment such that t50 of oocytes cultured in granulosa cell-conditioned medium was 152.5+/-19.0 min while that of oocytes cultured in M16 alone was 70.0+/-8.2 min. To see what molecular components of follicle cell-conditioned medium are involved in the above effects, the granulosa cell-conditioned medium was separated into two factions by using Microcon-10 membrane filter having a 10 kDa cut-off range. When denuded oocytes were cultured in medium containing the retentate, t50 of the oocytes was 70.0+/-10.5 min. In contrast, t50 of the denuded oocytes cultured in medium containing the filtrate was 142.0+/-26.5 min. T50 of denuded oocytes cultured in medium containing both retentate and filtrate was 188.0+/- 13.6 min. However, t50 of denuded oocytes cultured in M16 alone was 70.0 +/-11.0 min and that of oocytes cultured in whole granulosa cell-conditioned medium was 156.0+/-27.9 min. When surface membrane proteins of oocytes were electrophoretically analyzed, no difference was found between the protein profiles of oocytes cultured in M16 alone and of those cultured in the filtrate. CONCLUSIONS: Based upon these results, it is concluded that mouse follicle cells secrete a factor(s) which enhance the resistance of mouse oocytes against a proteolytic enzyme treatment. The factor appears to be a small molecules having a molecular weight less than 10 kDa.

Temporal Changes of c-fos, c-jun, and Heat Shock Protein 25 mRNA in Rat Uterus following Estradiol Treatment / 대한불임학회지

SUMMARY: Steroid hormone is known to cause the dynamic changes of mammalian uterus during reproductive cycle, which are modulated via hypothalamus-pituitary -gonad reproductive endocrine axis. Although there were so many studies about estrogenic regulation of uterine growth and differentiation. There is little information about the effect of estrogen on the expression of various transcription factors involved in gene expression. Thus the present study was designed to demonstrate E induced expression of c-fos, c-jun, hsp25 mRNA in rat uterus. Employing Northern blot analysis, we studied the temporal expressions of c-fos, c-jun, and hsp25 messenger RNAs (mNAs) elicited by a single 17beta-estradiol(E) treatment in the uteri of bilaterally ovariectomized adult rats. c-fos, c-jun, and hsp25 mRNA levels were increased and peaked at 3 h after E administration, and then c-fos and c-jun mRNA levels were rapidly decreased to basal control level while, increased hsp25 mRNA levels were sustained till 12 h post E treatment. To test the estrogenic effect on the increase of c-fos, c-jun, and hsp25 mRNA levels, we also examined the effects of antiestrogen (tamoxifen). Pretreatment with tamoxifen effectively blocked the E-induced increase of c-fos, c-jun, and hsp25 mRNA levels at 3 h post E treatment. Present results suggest that transient increase of c-fos and c-jun protooncogene mRNA at the early time and simultaneous expression of hsp25 mRNA contribute to the response of uterine tissues to E in adult female rats.

Effects of Somatic Cell Conditioned Medium on the Chymotrypsin Resistance of Mouse Oocytes / 대한불임학회지

Certain types of somatic cells, as well as follicular cumulus cells associating with mammalian oocytes, are known to produce beneficial effects on in vitro fertilization and preimplantation development of mammalian eggs when they are present in oocyte culture medium. To investigate the nature of the effects of somatic cells, the resistance of mouse oocytes against chymotrypsin treatment was examined after culture within various cell conditioned media. When mouse oocytes matured for 17-18 hr in the presence of cumulus cells were treated with 1% chymotrypsin, half of them remained still alive even after 240 min (t50>240.0). In contrast half of mouse oocytes cultured without cumulus cells underwent degeneration within 65.0 min (t50= 65.0+/-13.2 min) of the same treatment. To see if the effects were due to the secretory products of cumulus cells, mouse cumulus cells were cultured for 20 hr in medium containing 0.4% BSA and the supernatant of culture medium (conditioned medium) was taken. After maturation in the cumulus cell conditioned medium, mouse oocytes exhibited t50 = 190.0 +/-10.8 min upon chymotrypsin treatment whereas half of oocytes cultured without conditioned medium degenerated within 25.5 min. Human granulosa cell conditioned medium gave similar effects such that oocytes matured in conditioned medium exhibited t50 = 183.3+/-19.1 min while t50 of control group oocytes was 60.0+/-6.8 min. Oocytes matured in vero cell conditioned medium exhibited t50 = 196.7+/-8.8 min. On the other hand, amniotic cell conditioned medium resulted in the chymotrypsin resistance of t50 = 80.0+/-8.4 min which was not statistically different from the control value of t50 = 48.0+/-13.2 min. Based upon these results, it is suggested that certain somatic cell types including cumulus cells might change the biochemical properties of mouse oocyte membrane during meiotic maturation as revealed by the enhanced resistance against chymotrypsin treatment. Such effects of somatic cells appear to be mediated via the secretory products rather than direct communication between somatic cells and oocytes.

Effect of Steroid Hormones on the Expression of c-Fos, CREB, ATF, and HSP70 in Rat Uterus / 대한불임학회지

Steroid hormone is known to cause the dynamic changes of mammalian uterus during reproductive cycle. However there is little information about the effect of estrogen (E) and progesterone (P) on the expression of various transcription factors involved in gene expression. Thus the present study was designed to demonstrate E and/or P-induced expression of c-Fos, CREB, ATF and HSP70 in rat uterus. Rats, ovariectomized (OVX) for two weeks, were divided into 6 experimental groups, 1) OVX, 2) OVX+V, 3) OVX+E, 4) OVX+P, 5) OVX+E+V, 6) OVX+E+P, and western blotting assay for nuclear extract and immunohistochemical staining were carried out for each experimental group. Treatment of E (10microgram) showed to increase the expression of c-Fos, CREB, ATF, and HSP70, and maximal expression was occured at 3~6 hr after E administration. P (1mg) also increased, but much less than E, the expression of c-Fos, ATF, and HSP70. However, P did not reveal any effect on the expression CREB. P treatment 4 hr after E injection decreased c-Fos, CREB, and ATF expression, but did not show any change in the E-induced HSP70 expression. In immunohistochemical study c-Fos-, CREB-, and ATF-immunoreactivities were conficed to the cells of luminal epithelium of uterine endometrium. These results suggest that proliferation and differentiation of rat uterus during reproductive cycle may mediated via expression of transcription factors, such as c-Fos, CREB, ATF, and HSP70.

Effect of Seminal Vesicle Fluid Components on Acrosome Reaction of Mouse Epididymal Sperm / 대한불임학회지

This study aimed to evaluate the effect of seminal vesicle fluid (SVF) on the acrosome reaction (AR) occurred spontaneously or induced by Ca2+ ionophore A23187, follicular fluid, and progesterone in mouse epididymal sperm. SVF was divided into high (MW>10 kM)) and low (MW<10 kD) fractions by ultrafiltration. The low MW fraction of SVF decreased the rate of spontaneous AR, however the high MW fraction did not. It suggested that the low MW fraction of SVF might have contained decapacitation factor(s) responsible for prolonging of time need for capacitation. When sperm preincubated for 60 min in the presence of SVF, the rate of AR induced by A23187 was decreased, but prolongation of preincubation time for 120 min significantly potentiated the AR by A23187. It suggested that addition of SVF into sperm preincubation medium imposed the epididymal sperm a condition similar to ejaculation. AR induced by human follicular fluid or progesterone was also inhibited by SVF. It suggested that substance in SVF might have affected AR of mouse sperm by inhibiting the interaction between AR inducing ligands and sperm surface receptors involved in acrosomal exocytosis.

Studies on the lectin binding patterns of the oviduct luminal epithelium and oocytes in mouse / 대한불임학회지

No abstract available.

Mouse oviduct induces the changes of egg structure / 대한불임학회지

No abstract available.

A study on the activity of alkaline phosphatase of rat oviduct during early embryonic development / 대한불임학회지

No abstract available.