Acute dependence of ovarian progesterone output on the presence of placentas in 21-day pregnant rabbits.
Acute dependence of ovarian progesterone output on the presence of placentas in 21-day pregnant rabbits.
复制标题
怀孕 21 天的兔子卵巢孕酮输出对胎盘存在的急性依赖性。
作者：
J. Holt;L. Ewing
在家兔中研究了胎儿、胎盘和子宫在维持假妊娠期后妊娠内分泌状态中的作用。妊娠第21天，胎儿切除术后24小时，将胎盘留在原位时，孕酮和20±-羟基孕甾-4-烯-3-酮的全身血浆浓度和卵巢释放仍然很高。然而，当胎盘也被摘除时，孕酮的全身血浆浓度和卵巢释放在24小时内下降，而20±-羟基孕甾-4-烯-3-酮的全身血浆浓度和卵巢释放没有下降。切除整个妊娠子宫后，子宫黄体溶解素（Luteolysin，LH）的分泌明显减少，术后24小时，血浆孕酮浓度和卵巢孕酮释放量明显降低，但术后6小时，血浆孕酮浓度和卵巢孕酮释放量无明显变化。这些结果表明，在家兔妊娠第21天，母体卵巢孕酮的分泌急剧减少，而卵巢孕酮的分泌则明显减少。
The role of the fetuses, placentas and uterus in sustaining the endocrine status of preg-nancy beyond the duration of pseudopregnancy has been examined in the rabbit. Systemic plasma concentrations and ovarian release of progesterone and 20±-hydroxypregn-4-en-3-one remained high when placentas were left in situ 24 hr after fetectomy at day 21 of gestation. However, when the placentas also were extirpated, systemic plasma concentrations and ovarian release of progesterone declined within 24 hr, while systemic plasma concentrations and ovarian release of 20±-hy-droxypregn- 4-en-3-one did not decline. Removal of the entire gravid uterus and hence also pos-sible uterine luteolysin, resulted in decreased systemic plasma concentrations and ovarian release of progesterone 24 hr postoperatively, but not at 6 hr. These observations on systemic plasma concentrations and ovarian release of progestins establish that at day 21 of pregnancy in the rabbit, production of progesterone, by the maternal ovary, is acutely de...