Klandorf H, Lucini V, Harvey S
Gen Comp Endocrinol. 1984 Oct;56(1):140-5. doi: 10.1016/0016-6480(84)90070-4.
The metabolism of testosterone to reduced derivatives was studied in the pituitary gland, the hypothalamus, and the hyperstriatum dorsale of thyroidectomized, sham-operated, and thyroxine (T4)-injected immature cockerels. The levels of plasma thyroid hormones were markedly reduced (P less than 0.001) in thyroidectomized cockerels whereas thyroidectomized or sham-operated birds injected daily with 100 micrograms/kg thyroxine had significantly elevated (P less than 0.001) levels in comparison with sham-operated control birds. Each tissue was found to produce significant amounts of 5 beta-androstane-17 beta-ol-3-one (5 beta-DHT), 5 beta-androstane-3 alpha, 17 beta-diol (5 beta-3 alpha-diol), and androstenedione. Irrespective of thyroid state 5 beta-DHT and 5 beta-3 alpha-diol were produced to the greatest extent by the hyperstriatum dorsale whereas androstenedione was maximally produced in the pituitary gland. In comparison with the hyperstriatum dorsale and the hypothalamus only small quantities of 5 beta-DHT were produced in the pituitary gland. In the hyperstriatum dorsale of thyroidectomized birds both 5 beta-DHT (P less than 0.05) and 5 beta-3 alpha-diol (P less than 0.1) were formed to a greater extent than in sham-operated birds. This effect was reversed by administration of T4 to the operated birds which reduced the levels to those measured in the sham-operated controls. Similarly, injection of T4 into sham-operated birds decreased (P less than 0.05) the production of 5 beta-DHT in the hypothalamus while in the pituitary gland injection of T4 into thyroidectomized birds reduced the production of androstenedione (P less than 0.05). It was concluded that in the cockerel thyroid hormone is likely to play a role in the metabolism of testosterone. The physiological significance of 5 beta-reductase activity in the neuroendocrine tissues is discussed.
在甲状腺切除、假手术以及注射甲状腺素（T4）的未成熟公鸡的垂体、下丘脑和背侧上纹状体中，研究了睾酮向还原衍生物的代谢情况。甲状腺切除的公鸡血浆甲状腺激素水平显著降低（P<0.001），而每天注射100微克/千克甲状腺素的甲状腺切除或假手术的鸡，其甲状腺激素水平与假手术对照鸡相比显著升高（P<0.001）。发现每个组织都能产生大量的5β-雄烷-17β-醇-3-酮（5β-DHT）、5β-雄烷-3α,17β-二醇（5β-3α-二醇）和雄烯二酮。无论甲状腺状态如何，背侧上纹状体产生5β-DHT和5β-3α-二醇的量最大，而垂体中雄烯二酮的产生量最大。与背侧上纹状体和下丘脑相比，垂体中产生的5β-DHT量较少。在甲状腺切除鸡的背侧上纹状体中，5β-DHT（P<0.05）和5β-3α-二醇（P<0.1）的生成量比假手术鸡更多。对手术鸡施用T4可逆转这种效应，使水平降至假手术对照鸡所测水平。同样，向假手术鸡注射T4会降低下丘脑5β-DHT的产生（P<0.05），而向甲状腺切除鸡的垂体注射T4会降低雄烯二酮的产生（P<0.05）。得出的结论是，在公鸡中甲状腺激素可能在睾酮代谢中起作用。讨论了神经内分泌组织中5β-还原酶活性的生理意义。
