促黄体生成素刺激的大鼠睾丸胞质组分对正常大鼠睾丸线粒体孕烯醇酮生成的影响。

Effect of cytosol fractions from lutropin-stimulated rat testes on pregnenolone production by mitochondria from normal rat testes.

作者信息

Bakker C P, van der Plank-van Winsen M P, van der Molen H J

出版信息

Biochim Biophys Acta. 1978 Oct 3;543(2):235-42. doi: 10.1016/0304-4165(78)90068-5.

Abstract

The rate limiting step in the production of steroids in the testis is the mitochondrial conversion of cholesterol to pregnenolone. This conversion can be stimulated by lutropin, but the precise interaction between lutropin-induced cytoplasmic factors and the mitochondrial activity in steroid production is as yet unknown. The results described in the present paper concern the steroid production of isolated mitochondrial fractions in recombination experiments with isolated supernatant fractions from total testes homogenates. Cyanoketone as well as SU-10603, an inhibitor of steroid 17 alpha-hydroxylase activity are required to block pregnenolone metabolism. The results show that the cytoplasm contains lutropin-induced factor(s) which can exert its effect in vitro on the cholesterol side-chain cleavage activity in intact mitochondria isolated from control testes.

摘要

睾丸中类固醇生成的限速步骤是胆固醇在线粒体中转化为孕烯醇酮。这种转化可被促黄体激素刺激，但促黄体激素诱导的细胞质因子与类固醇生成中线粒体活性之间的确切相互作用尚不清楚。本文所述结果涉及在与来自全睾丸匀浆的分离上清液部分进行重组实验时，分离的线粒体部分的类固醇生成。需要氰基酮以及类固醇17α-羟化酶活性抑制剂SU-10603来阻断孕烯醇酮的代谢。结果表明，细胞质中含有促黄体激素诱导因子，其在体外可对从对照睾丸分离的完整线粒体中的胆固醇侧链裂解活性产生影响。