Acute immobilization stress disrupts testicular steroidogenesis in adult male rats by inhibiting the activities of 17 alpha-hydroxylase and 17,20-lyase without affecting the binding of LH/hCG receptors.
Acute immobilization stress disrupts testicular steroidogenesis in adult male rats by inhibiting the activities of 17 alpha-hydroxylase and 17,20-lyase without affecting the binding of LH/hCG receptors.
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DOI：
10.1002/j.1939-4640.1994.tb00455.x
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发表时间：
1994-07
影响因子：
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通讯作者：
T. Orr;Taylor Mf;Bhattacharyya Ak;Collins Dc;David R. Mann
中科院分区：
文献类型：
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作者：
T. Orr;Taylor Mf;Bhattacharyya Ak;Collins Dc;David R. Mann
我们研究了急性制动（3小时）应激对成年大鼠睾丸类固醇生成的影响。制动并没有改变血浆黄体生成素（LH）水平，但血浆睾酮（T）水平下降了82%。应激大鼠的血浆皮质酮水平比对照水平升高了9倍多。在3小时的应激后，与对照组相比，睾丸孕酮水平升高了33%，17 α-羟孕酮和T水平分别降低了47%和37%。固定3小时对睾丸间质细胞LH/人绒毛膜促性腺激素（hCG）受体的结合或解离速率常数没有影响，也没有改变特异性hCG结合。通过在存在21[14 C]孕酮和[3 H]17 α-羟孕酮的情况下孵育应激和对照动物的睾丸微粒体，评估固定3小时对睾丸17 α-羟化酶和17，20-裂解酶的影响。大鼠的固定使17 α-羟化酶和17，20-裂解酶的Vmax值分别降低了47%和48%，但对Km值没有影响。这些结果支持这一假设，即3小时的压力破坏大鼠睾丸类固醇通过一种机制，是独立的LH的循环水平和LH/hCG受体的结合特性的变化。制动对睾丸类固醇含量和17 α-羟化酶和17，20-裂解酶活性的影响表明，应激抑制17 α-羟化酶和17，20-裂解酶的活性。
We have investigated the effect of acute immobilization (3 hours) stress on testicular steroidogenesis in the adult rat. Immobilization did not alter plasma luteizing hormone (LH) levels, but plasma testosterone (T) levels were reduced by 82%. Plasma levels of corticosterone in stressed rats were elevated more than ninefold over control levels. After 3 hours of stress, testicular levels of progesterone were elevated 33%, and levels of 17 alpha-hydroxyprogesterone and T were reduced 47% and 37%, respectively, compared to controls. Immobilization for 3 hours had no effect on the association or dissociation rate constants of LH/human chorionic gonadotropin (hCG) receptors of testicular interstitial cells and did not alter specific hCG binding. The effect of 3 hours of immobilization on testicular 17 alpha-hydroxylase and 17,20-lyase was assessed by incubating testicular microsomes from stressed and control animals in the presence of 21[14C]progesterone and [3H]17 alpha-hydroxyprogesterone. Immobilization of rats reduced the Vmax values of 17 alpha-hydroxylase and 17,20-lyase by 47% and 48%, respectively, but had no effect on the Km values. These results support the hypothesis that stress for 3 hours disrupts rat testicular steroidogenesis via a mechanism that is independent of changes in circulating levels of LH and the binding characteristics of LH/hCG receptors. The effects of immobilization on the content of testicular steroids and on the activities of 17 alpha-hydroxylase and 17,20-lyase suggest that stress inhibits the activities of both 17 alpha-hydroxylase and 17,20-lyase.