【摘要】 近期研究提示,黄体萎缩（溶解）与细胞凋亡有关.但是影响细胞凋亡的因素还不清楚.我们以往的工作表明,抑制素α亚单位-N末端片段[Tyr]-1-32(P³³)显著抑制大鼠黄体细胞孕酮分泌.本研究应用PMSG-hCG诱导大鼠的假孕模型进一步观察P³³以及其他因素对黄体细胞凋亡的作用.未成年大鼠注射65IU PMSG,48h后注射hCG50IU.于hCG注射第5天用P³³（40μg/只）,P²⁹（37～65氨基酸）（50μg/只）,催产素（oxytocin.OT）（40μg/只）.Tyr（1.5mg/只）和E₂（1.5mg/只）每日一次:PGF_2α（12.5μPg/只）隔日注射.共注3次.于hCG注射第12天断头取血、卵巢.P³³,P²⁹.OT,PG_2α和Tyr处理组大鼠血浆雌激素、孕酮水平下降.E₂处理组则血浆雌激素、孕酮水平上升.提取DNA、定量、电泳分析显示.细胞核孵育后则可见清晰梯形条带.P³³.P²⁹.OT、PGF_2α和Tyr组直接提取或细胞核孵育后提取的低分子量DNA均增加.相反雌激素抑制低分子量DNA的产生.结果揭示、P²⁹,P³³、OT.PGF_2α.Tyr和雌激素在调节共黄体萎缩中起重要作用.P²⁹,P³³,OT.PGF_2α.Tyr诱导大鼠黄体细胞介导凋亡的核酸内切酶的表达,促进黄体细胞凋亡;雌激素抑制黄体细胞凋亡.本结果对进一步探讨黄体细胞凋亡机制奠定了基础.更多还原

【Abstract】 At the end of a nonconception estrous cycle, the corpus luteum undergoes luteolysis. Recentstudies have suggested that luteolysis is associated with cell apoptosis, but the factors affecting cell apoptosis are not well defined. Our previous work demonstrated that human inhibin a - N -terminal fragments Tyr -1-32 （P33） significantly inhibited progesterone production by rat corpus luteal cells. In this study, we used PMSG - hCG -induced pseudopregnant model to further observe the effects of P33 and other factors on modulating corpus luteal cell apoptosis. Immature female rats were injected 65 IU PMSG, followed by 50 IU hCG 48 h later. On day 5 after hCG injection,experimental groups were received daily injection of a inhibin [Tyr]l - 32（P33, 40 μg/ rat）, a inhibin N - 37 - 65（P²950 fxg/rat）, tyrosine （Tyr, 1. 5 ing/rat） and estrogen （1,5 mg/ rat） respectively for 7 days; daily injection of oxytocin （OT, 40μ g/rat） for 5 days; every two days injection of PGF₂a（12. 5 μg/rat） for three times. On day 12, the rats from all the groups were killed, trunk bloods were collected and corpus lutea (CD were taken. Serum E₂ and P₄ levels in P33, P29, OT, PGF₂a and Tyr treated groups decreased and in estrogen treated group increased significantly. Accordingly, DNA was isolated from CL and the LMW DNA contents was calculated and the pattern of fragmented DNA in cell lysates was examined after gel electrophoresis. The results showed the ladder pattern of DNA could be visible in all of the groups after nucleus incubation. P³3, P29, OT, PGF₂a and Tyr promoted LMW DNA production. In contrast, estrogen inhibited LMW DNA production. Above all, these data suggested that P29, P³3, OT, PGF²9, Tyr and estrogen play an important role in modulating luteoregression, with P33, P²9, OT, PGF₂a,Tyr and estrogen play an important role in modulating luteoregression, with P33,P²9,OT,PGF₂a,Tyr promoting apoptosis and estrogen inhibiting apoptosis. These data provided a basis for further studies on the mechanisma that regulate corpus luteal cell apoptosis.更多还原