Differential effects of luteinizing hormone-releasing hormone on follicle-stimulating hormone-dependent responses in rat granulosa cells and Sertoli cells in vitro.
Differential effects of luteinizing hormone-releasing hormone on follicle-stimulating hormone-dependent responses in rat granulosa cells and Sertoli cells in vitro.
复制标题
黄体生成素释放激素对体外大鼠颗粒细胞和支持细胞促卵泡激素依赖性反应的不同影响。
作者：
R. Gore;M. Lacroix;J. Dorrington
本文比较了LHRH和LHRH激动剂（[D-Ser-（But），6，des-Gly-NH_（210）] LHRH乙基酰胺）抑制大鼠颗粒细胞和支持细胞FSH反应的能力。从22或25日龄的己烯雌酚致敏大鼠中分离出颗粒细胞，并在规定条件下与NIH-FSH-S13（300 ng/ml）或霍乱毒素（0.1 μ g/ml）一起培养48 h，结果显示芳香化酶活性增加，这通过[1 β-3H]睾酮释放3H2O来确定。LHRH（10（-7）M）或TH激动剂（10（-8）M）与FSH或霍乱毒素同时加入，可抑制对~3H_2O释放的影响，而不影响细胞培养物的蛋白质含量。一个较小的刺激3H2O生产发生（Bu）2cAMP（1.0 mM）加3-异丁基-1-甲基黄嘌呤（0.1 mM），这是部分抑制LHRH或激动剂的存在下。用来自15或20日龄大鼠的支持细胞进行的平行研究表明，在适当条件下用FSH、霍乱毒素或（Bu）2cAMP（0.5 mM）培养24 h可引起细胞芳香化酶活性增加，并增强纤溶酶原激活剂向培养基中的分泌。然而，当同时或在刺激剂之前24小时加入肽时，LHRH（10（-7）或10（-9）M）或激动剂（10（-6）或10（-8）M）没有抑制作用。同样，从11日龄大鼠的Sertoli细胞处理LHRH激动剂每天培养5天，显示没有抑制芳香化酶活性后4小时的刺激与FSH或（Bu）2cAMP。用或不用10（-8）M LHRH激动剂培养5天后，芳香化酶活性的FSH剂量-反应曲线（0 - 300 ng/ml）相似，表明LHRH不会引起对FSH敏感性的改变。在37 ℃或32 ℃下培养的Sertoli细胞中观察到缺乏抑制作用.用于分离Sertoli细胞的酶消化方法不是LHRH作用缺乏的原因，因为在没有蛋白水解酶的帮助下制备的细胞培养物在存在或不存在10（-8）M激动剂的情况下显示出类似的FSH刺激芳香酶活性。此外，当与支持细胞培养物一起孵育时，没有证据表明LHRH激动剂降解。从这些研究中，我们得出结论：1）颗粒细胞和支持细胞从未成熟的大鼠在他们的反应不同的LHRH，和2）未成熟的支持细胞是一个不太可能的目标，LHRH对精子发生的直接抑制作用。
The abilities of LHRH and a potent LHRH agonist ([D-Ser-(But),6, des-Gly-NH210]LHRH ethylamide) inhibit FSH responses by rat granulosa cells and Sertoli cells in vitro have been compared. Granulosa cells isolated from 22- or 25-day-old diethylstilbestrol-primed rats and cultured under defined conditions for 48 h with NIH-FSH-S13 (300 ng/ml) or cholera toxin (0.1 microgram/ml) showed increased aromatase activity, as determined by the release of 3H2O from [1 beta-3H]testosterone. LHRH (10(-7) M) or th agonist (10(-8) M) added simultaneously with FSH or cholera toxin inhibited the effects on the release of 3H2O without influencing the protein content of the cell cultures. A smaller stimulation of 3H2O production occurred with (Bu)2cAMP (1.0 mM) plus 3-isobutyl-l-methylxanthine (0.1 mM), and this was partially suppressed in the presence of LHRH or the agonist. Parallel studies with Sertoli cells from 15- or 20-day-old rats demonstrated that culture under appropriate conditions with FSH, cholera toxin, or (Bu)2cAMP (0.5 mM) for 24 h caused an increase in cellular aromatase activity and enhanced secretion into the medium of plasminogen activator. However, no inhibition by LHRH (10(-7) or 10(-9) M) or the agonist (10(-6) or 10(-8) M) occurred when the peptides were added either simultaneously or 24 h before the stimulatory agent. Similarly, Sertoli cells from 11-day-old rats treated daily with LHRH agonist for 5 days in culture, showed no inhibition of aromatase activity after a 4-h stimulation with FSH or (Bu)2cAMP. FSH dose-response curves (0-300 ng/ml) for aromatase activity were shown to be similar after 5 days of culture with or without 10(-8) M LHRH agonist, indicating that the LHRH did not cause a shift in the sensitivity to FSH. The lack of inhibition was seen in Sertoli cell cultures maintained at 37 or 32 C. The enzyme digestion method used to isolated Sertoli cells was not responsible for the lack of effects of LHRH, since cell cultures prepared without the aid of proteolytic enzymes showed similar FSH stimulation of aromatase activity in the presence or absence of 10(-8) M agonist. Further, there was no evidence of degradation of the LHRH agonist when incubated with Sertoli cell cultures. From these studies, we conclude that 1) granulosa cells and Sertoli cells from immature rats differ in their responses to LHRH, and 2) the immature Sertoli cell is an unlikely target for a direct inhibiting influence of LHRH on spermatogenesis.