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To compare the expression patterns of steroid receptor coactivators (SRCs) and steroid-induced stromal cell-derived factor 1 (CXCL12 (SDF1)) in normal and ectopic endometrium and to explore the roles of NCOA1 (SRC1) and NCOA2 (SRC2) in the steroid-induced CXCL12 expression in normal and ectopic endometrial stromal cells (ESCs). The NCOA1, NCOA2, NCOA3 (SRC3), and CXCL12 (SDF1)α mRNA levels in normal and ectopic endometrium were analyzed by quantitative real-time PCR. Steroid-induced CXCL12 expression was detected by the ELISA method and the chemotactic activity of conditioned supernatant to monocyte was assessed by the Boyden chamber method before and after the silencing of NCOA1 or NCOA2 with siRNA in normal and ectopic ESCs. The expression of NCOA1 and CXCL12 in ectopic endometrium was significantly greater than that in normal endometrium in the secretory phase. Progesterone (P₄) was able to significantly inhibit estradiol (E₂)-stimulated CXCL12 expression in normal and ectopic ESCs. The inhibitory rate of P₄ in ectopic ESCs at 72 and 96 h was significantly lower than that in normal ESCs. Silencing of NCOA1 but not NCOA2 significantly reduced the E₂-induced CXCL12 expression in normal and ectopic ESCs. The ability of P₄ to inhibit E₂-induced CXCL12 expression and monocyte chemotaxis in normal and ectopic ESCs was significantly attenuated when NCOA2 was silenced. NCOA1 plays a necessary role in E₂-induced CXCL12 expression and NCOA2 is required for P₄ to inhibit the E₂-induced CXCL12 production in normal and ectopic endometrium.

CD9 is a cell surface protein that participates in many cellular processes, such as cell adhesion. Fertilization involves sperm and oocyte interactions including sperm binding to oocytes and sperm–oocyte fusion. Thus CD9 may play an essential role during fertilization in mammals. The present study was conducted to examine whether CD9 is present in porcine gametes and whether it participates in the regulation of sperm–oocyte interactions. The presence of CD9 in ovarian tissues, oocytes and spermatozoa was examined by immunohistochemistry, immunofluorescence and immunoblotting. Sperm binding and penetration of oocytes treated with CD9 antibody were examined by in vitro fertilization. The results showed that CD9 was present on the plasma membrane of oocytes at different developmental stages. A 24 kDa protein was found in oocytes during in vitro maturation by immunoblotting and its quantity was significantly (P < 0.001) increased as oocytes underwent maturation and reached the highest level after the oocytes had been cultured for 44 h. No positive CD9 staining was found in the spermatozoa. Both sperm binding to ooplasma and sperm penetration into oocytes were significantly (P < 0.01) reduced in anti-CD9 antibody-treated oocytes (1.2 ± 0.2 per oocyte and 16.6% respectively) as compared with oocytes in the controls (2.5 ± 0.4 per oocyte and 70.3% respectively). These results indicated that CD9 is expressed in pig oocytes during early growth and meiotic maturation and that it participates in sperm–oocyte interactions during fertilization.

The present study was designed to investigate the localization and function of cytoplasmic dynein (dynein) during mouse oocyte meiosis and its relationship with two major spindle checkpoint proteins, mitotic arrest-deficient (Mad) 1 and Mad2. Oocytes at various stages during the first meiosis were fixed and immunostained for dynein, Mad1, Mad2, kinetochores, microtubules, and chromosomes. Some oocytes were treated with nocodazole before examination. Anti-dynein antibody was injected into the oocytes at germinal vesicle (GV) stage before the examination of its effects on meiotic progression or Mad1 and Mad2 localization. Results showed that dynein was present in the oocytes at various stages from GV to metaphase II and the locations of Mad1 and Mad2 were associated with dynein’s movement. Both Mad1 and Mad2 had two existing states: one existed in the cytoplasm (cytoplasmic Mad1 or cytoplasmic Mad2), which did not bind to kinetochores, while the other bound to kinetochores (kinetochore Mad1 or kinetochore Mad2). The equilibrium between the two states varied during meiosis and/or in response to the changes of the connection between microtubules and kinetochores. Cytoplasmic Mad1 and Mad2 recruited to chromosomes when the connection between microtubules and chromosomes was destroyed. Inhibition of dynein interferes with cytoplasmic Mad1 and Mad2 transportation from chromosomes to spindle poles, thus inhibits checkpoint silence and delays anaphase onset. These results indicate that dynein may play a role in spindle checkpoint inactivation.

Summary. Cell suspensions were prepared from human corpora lutea obtained during the mid-luteal phase. Progesterone production was assessed after short-term incubation of luteal cell suspensions. Luteal cells were very sensitive to hCG, the concentration required for 50% maximum response being 0·01 i.u./ml, and the response was 5 times higher than the basal production.

Oestradiol (1–100 μm) induced a significant dose-related decrease in both basal and hCG-stimulated progesterone production. The A-nor steroidal compounds anordrin and AF-45 reduced hCG-stimulated progesterone production only at the high concentration of 100 μm. The ED50 values were approximately 3 μm, 75 μm and 100 μm for oestradiol, AF-45 and anordrin respectively. Anordrin showed no significant effects on basal progesterone production. In addition, oestradiol markedly inhibited the activity of 3β-hydroxysteroid dehydrogenase in luteal cells, expressed by the conversion of pregnenolone to progesterone, but the inhibitory effects of anordrin and AF-45 were negligible or relatively low.

The effects of anordrin and AF-45 were different from those of oestradiol on progesterone production by human luteal cells in vitro, indicating that neither substance is likely to be a useful luteolytic agent in women.

Keywords: A-nor steroid; oestradiol; luteal cells; progesterone; 3β-hydroxysteroid dehydrogenase; man

This study was designed to examine the effect of Taxol pretreatment on vitrification of porcine oocytes matured in vitro by an open pulled straw (OPS) method. In the first experiment, the effect of Taxol pretreatment and fluorescein diacetate (FDA) staining on parthenogenetic development of oocytes was evaluated. In the second experiment, viability, microtubule organization and embryo development of oocytes were assessed after oocytes were exposed to vitrification/warming solutions or after vitrification with or without Taxol pretreatment. The results showed that Taxol pretreatment and/or FDA staining did not negatively influence the oocyte’s developmental competence after parthenogenetic activation. After being exposed to vitrification/warming solutions, the survival rate (83.3%) of the oocytes was significantly (P < 0.05) reduced as compared with that in the control (100%). Vitrification/warming procedures further reduced the survival rates of oocytes regardless of oocytes being treated with (62.1%) or without (53.8%) Taxol. The proportions of oocytes with normal spindle configuration were significantly reduced after the oocytes were exposed to vitrification/warming solutions (38.5%) or after vitrification with (10.3%) or without (4.1%) Taxol pretreatment as compared with that in control (76.8%). The rates of two-cell-stage (5.6–53.2%) embryos at 48 h and blastocysts (0–3.8%) at 144 h after activation were significantly reduced after exposure to vitrification/warming solutions or after vitrification as compared with control (90.9% and 26.6% respectively). However, the proportion of vitrified oocytes developed to two-cell stage was significantly higher when oocytes were pretreated with (24.3%) than without (5.6%) Taxol. These results indicate that pretreatment of oocytes with Taxol before vitrification helps to reduce the damage induced by vitrification and is a potential way to improve the development of vitrified porcine oocytes.