Hamel R, Savoie S, Collu R, Saez J M, Bertrand J, Ducharme J R
Horm Res. 1983;18(4):198-205. doi: 10.1159/000179795.
The in vivo and in vitro testicular responsiveness to hCG of hemicastrated lamb fetuses 95-99, 110-118 and 130-141 days of gestational age was studied. Basal plasma testosterone (T) levels were similar at all ages (less than 0.25 ng/ml), while the mean testicular concentrations of dehydroepiandrosterone sulfate (DHA-S), 17 alpha-hydroxyprogesterone (17-OHP) and T were higher in 95- to 99-day-fold fetuses. Plasma T levels and the concentration of T, DHA-S, 17-OHP, androstenedione (A) and cyclic adenosine 3'5'-monophosphate (cAMP) were increased by hCG in the hemicastrated animal at all ages. cAMP and T production by enriched preparations of dispersed interstitial cells from control testes was increased by hCG in all groups. In fetuses pretreated with hCG in vivo the addition of hCG in vitro failed to modify cAMP and T production. 100 micrograms of LHRH to a 130-day-old fetus increased plasma LH and T levels. From these experiments, it is suggested that the low plasma LH and T levels found throughout the last trimester of fetal life reflect a relative lack of endogenous LHRH synthesis and/or release, rather than reduced testicular steroidogenic capacity.
研究了95 - 99日龄、110 - 118日龄和130 - 141日龄半阉割羔羊胎儿睾丸对人绒毛膜促性腺激素（hCG）的体内和体外反应性。所有年龄段的基础血浆睾酮（T）水平相似（低于0.25 ng/ml），而95至99日龄胎儿的睾丸硫酸脱氢表雄酮（DHA - S）、17α - 羟孕酮（17 - OHP）和T的平均浓度较高。在所有年龄段的半阉割动物中，hCG均可使血浆T水平以及T、DHA - S、17 - OHP、雄烯二酮（A）和环磷酸腺苷（cAMP）的浓度升高。在所有组中，hCG均可使来自对照睾丸的分散间质细胞富集制剂产生的cAMP和T增加。在体内经hCG预处理的胎儿中，体外添加hCG未能改变cAMP和T的产生。给130日龄胎儿注射100微克促性腺激素释放激素（LHRH）可使血浆促黄体生成素（LH）和T水平升高。从这些实验推测，在胎儿期最后三个月发现的低血浆LH和T水平反映的是内源性LHRH合成和/或释放相对不足，而非睾丸类固醇生成能力降低。
