Cellular observations and hormonal correlates of feedback control of luteinizing hormone secretion by testosterone in long-term castrated male rhesus monkeys.
Cellular observations and hormonal correlates of feedback control of luteinizing hormone secretion by testosterone in long-term castrated male rhesus monkeys.
复制标题
长期去势雄性恒河猴中睾酮对黄体生成素分泌的反馈控制的细胞观察和激素相关性。
DOI：
10.1095/biolreprod63.3.872
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发表时间：
2000
影响因子：
3.6
通讯作者：
Roselli,CE
中科院分区：
文献类型：
--
作者：
Resko,JA;Pereyra-Martinez,AC;Stadelman,HL;Roselli,CE
生理水平的睾酮对长期去势雄猴LH分泌无负反馈作用。这种不应性的细胞基础尚不清楚。为了研究它，我们比较了两组雄性恒河猴：一组（组1，n = 4）被阉割，并立即用睾酮治疗30天;第二组（组2，n = 4）被阉割，并在阉割后21天开始用睾酮治疗9天。第1组睾酮对LH的反馈控制是正常的，而第2组对其作用不敏感。以下丘脑视前区内侧和基底区内侧芳香化酶活性（P450 AROMmRNA）和雄激素受体mRNA浓度为终点，发现组2的芳香化酶活性显著低于组1，P< 0.01。而P450 AROMmRNA和雄激素受体mRNA则无明显差异。我们的数据表明，长期去势后睾酮不敏感的细胞基础可能在于特定脑区芳香化睾酮的能力降低。由于P450 AROMmRNA在第2组雄性中没有变化，我们假设在长期去势的猴子中发生了雌激素依赖性神经缺陷，不涉及P450 AROMmRNA的调节。
Testosterone at physiological levels cannot exert negative feedback action on LH secretion in long-term castrated male monkeys. The cellular basis of this refractoriness is unknown. To study it, we compared two groups of male rhesus macaques: one group (group 1, n = 4) was castrated and immediately treated with testosterone for 30 days; the second group (group 2, n = 4) was castrated and treated with testosterone for 9 days beginning 21 days after castration. Feedback control of LH by testosterone in group 1 was normal, whereas insensitivity to its action was found in group 2. Using the endpoints of concentrations of aromatase activity (P450AROMmessenger RNA [mRNA]) and androgen receptor mRNA in the medial preoptic anterior hypothalamus and in the medial basal hypothalamus, we found that aromatase activity in both of these tissues was significantly lower,P< 0.01, in group 2 compared with group 1 males. P450AROMmRNA and androgen receptor mRNA did not differ, however. Our data suggest that the cellular basis of testosterone insensitivity after long-term castration may reside in the reduced capacity of specific brain areas to aromatize testosterone. Because P450AROMmRNA did not change in group 2 males, we hypothesize that an estrogen-dependent neural deficit, not involving the regulation of the P450AROMmRNA, occurs in long-term castrated monkeys.