Coniglio J G, Marzouki Z M, Sharp J
Department of Biochemistry, Vanderbilt University, Nashville, Tennessee 37232.
Arch Androl. 1988;20(3):193-201. doi: 10.3109/01485018808987073.
Effect of hypophysectomy on fatty acid elongation was investigated in isolated rat testicular microsomes incubated with [14C]malonyl CoA. Hypophystectomy resulted in a 40% decrease in total incorporation of 14C into fatty acids of microsomes. Several 18- and 20-carbon fatty acids of testicular microsomes from hypophysectomized rats had less 14C than did those from nonhypophysectomized ones, whereas only docosa-7,10,13,16-tetraenoic acid (22:4w6) had more 14C. Testosterone injected subcutaneously into hypophysectomized rats at a dose of 0.5 mg per day for eight days posthypophysectomy had no apparent effect on either the total 14C incorporated or the distribution of the 14C in the various fatty acids. Daily subcutaneous injections of 50 or 100 micrograms follicle stimulating hormone (FSH) had some effect on both total incorporation and distribution of 14C. Addition of 0.5 mg testosterone to the 50 micrograms FSH gave the same results as the FSH alone. Smaller amounts of stearic acid (18:0) and linoleic acid (18:2) and increased amounts of docosa-4,7,10,13,16-pentaenoic acid (22:5w6) were present in the microsomes of hypophysectomized compared to nonhypophysectomized rats. Testosterone replacement did not affect these differences, but FSH administration was partially effective in altering the values toward those observed in nonhypophysectomized rats. Results obtained in these experiments indicate that there is inhibition of the testicular microsomal fatty acid elongation system in hypophysectomized rats and that, although testosterone is not at all effective in relieving the inhibition, FSH administration is at least partly effective.
在与[14C]丙二酰辅酶A一起孵育的离体大鼠睾丸微粒体中，研究了垂体切除对脂肪酸延长的影响。垂体切除导致微粒体脂肪酸中14C的总掺入量减少40%。垂体切除大鼠睾丸微粒体中的几种18碳和20碳脂肪酸所含的14C比未垂体切除大鼠的少，而只有二十二碳-7,10,13,16-四烯酸（22:4ω6）所含的14C更多。垂体切除后8天，以每天0.5毫克的剂量皮下注射睾酮给垂体切除大鼠，对14C的总掺入量或其在各种脂肪酸中的分布均无明显影响。每天皮下注射50或100微克促卵泡激素（FSH）对14C的总掺入量和分布均有一定影响。在50微克FSH中添加0.5毫克睾酮得到的结果与单独使用FSH相同。与未垂体切除大鼠相比，垂体切除大鼠的微粒体中硬脂酸（18:0）和亚油酸（18:2）含量较少，而二十二碳-4,7,10,13,16-五烯酸（22:5ω6）含量增加。睾酮替代并未影响这些差异，但给予FSH可部分有效地使这些值朝着未垂体切除大鼠中观察到的值改变。这些实验获得的结果表明，垂体切除大鼠的睾丸微粒体脂肪酸延长系统受到抑制，并且，虽然睾酮完全不能有效缓解这种抑制，但给予FSH至少部分有效。
