Gonadotropin-releasing hormone effects on placental hormones during gestation: I. Alpha-human chorionic gonadotropin, human chorionic gonadotropin and human chorionic somatomammotropin.
Gonadotropin-releasing hormone effects on placental hormones during gestation: I. Alpha-human chorionic gonadotropin, human chorionic gonadotropin and human chorionic somatomammotropin.
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妊娠期间促性腺激素释放激素对胎盘激素的影响：I.α-人绒毛膜促性腺激素、人绒毛膜促性腺激素和人绒毛膜生长激素。
DOI：
10.1095/biolreprod34.2.245
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发表时间：
1986
影响因子：
3.6
通讯作者：
Rhode,J
中科院分区：
文献类型：
--
作者：
Siler-Khodr,TM;Khodr,GS;Valenzuela,G;Rhode,J
本文研究了不同胎龄胎盘体外释放α-人绒毛膜促性腺激素（α hCG）、人绒毛膜促性腺激素（hCG）和人绒毛膜促生长激素（hCS）的情况。促性腺激素释放激素（GnRH）对这些激素释放的影响与胎盘培养胎龄和GnRH剂量有关，αhCG和hCG的基础释放量在孕9-13周最大（分别为1000-1500 ng/mg和250-350 ng/mg）。最低的释放率是在足月时（分别为28纳克/毫克和20纳克/毫克）。激素释放下降，延长文化，除了从文化的13和15周的胎盘，其中最初的高释放持续整个8天的文化。hCS的初始释放在6周时较低，到15周时增加到最大速率，与足月时的初始释放速率相似。促性腺激素释放激素刺激16周和17周胎盘培养物中αhCG和hCG的释放最显著，分别增加400倍和250倍。在培养的第6天观察到（p<0.0001）。在体外培养6天的足月胎盘中，GnRH可使α hCG刺激20倍，hCG增加10倍（p<0.001）。在雌激素水平较低时，αhCG和hCG对GnRH的反应最大。在某些胎盘中观察到剂量相关反应，但在某些情况下，在这些研究中使用的所有剂量（0.2至50 μg/ml）下均达到最大效应。这些数据还表明，合成GnRH能够刺激αhCG和hCG的产生，但对GnRH刺激的反应程度和模式与胎盘组织的胎龄及其培养时间有关。对外源性GnRH刺激αhCG和hCG释放的最敏感期是培养的第5天和第6天，此时基础雌激素释放非常低。这些数据支持hCG释放可能受绒毛膜GnRH刺激控制的假设，并表明局部类固醇水平可能调节hCG对GnRH刺激的反应。
The release of α-human chorionic gonadotropin (α hCG), gonadotropin human chorionic gonadotropin (hCG) and human chorionic somatomammotropin (hCS) in vitro from placentas of different gestational ages was studied. In addition, the effect of gonadotropin-releasing hormone (GnRH) on these hormonal releases, as related to the gestational age of the placenta cultured and the dose of GnRH, was determined.The basal release of αhCG and hCG was greatest at 9–13 wk of gestation (1000–1500 ng/mg and 250–350 ng/mg, respectively). Lowest release rates were at term (28 ng/mg and 20 ng/mg, respectively). Hormonal release declined with extended culture, except from the cultures of 13- and 15-wk placentas, in which the initially high release continued throughout the 8 days of culture. The initial release of hCS was low at 6 wk, increased to maximum rates by 15 wk, and was similar to the initial rate of release at term.Gonadotropin-releasing hormone stimulated the release of αhCG and hCG most dramatically in cultures of 16-wk and 17-wk placentas, where as much as a 400- and 250-fold increase, respectively, on Day 6 of culture was observed (p<0.0001). In term placenta cultures after 6 days in vitro, a 20-fold stimulation of α hCG and a 10-fold increase of hCG was effected by GnRH (p<0.001). The largest responses of αhCG and hCG to GnRH were observed when estrogen levels were low. Dose-related responses were observed in some placentas, yet in some instances, maximal effects were attained with all doses utilized in these studies (0.2 to 50 μg/ml).These data demonstrate that human placentas of different gestational ages have varying hormonogenic capabilities in vitro. The data also establish that synthetic GnRH is capable of stimulating αhCG and hCG production, but the degree and pattern of response to GnRH stimulation are related to the gestational age of the placental tissue and its time in culture. The most responsive period to exogenous GnRH stimulation of αhCG and hCG release was on Days 5 and 6 of culture, when basal estrogen release was very low. These data support the hypothesis that hCG release might be controlled by a chorionic GnRH stimulation and suggest that local steroid levels may modulate the hCG response to GnRH stimulation.