The inhibitory effects of ACTH and adrenalectomy on reproductive maturation in female rats.
The inhibitory effects of ACTH and adrenalectomy on reproductive maturation in female rats.
复制标题
ACTH和肾上腺切除术对雌性大鼠生殖成熟的抑制作用。
作者：
L. A. Macfarland;D. Mann
研究了促肾上腺皮质激素和肾上腺切除术对雌性大鼠性成熟的影响。断奶（21日龄）完整和去肾上腺的雌性大鼠给予4 IU/100 gm体重，直至第40天。动物于第25、30、35、40天和阴道开放当天处死。检测血液中黄体酮、皮质酮、黄体生成素和催乳素的含量。在第一次发情时处死的动物，检查输卵管中存在的卵子数量。ACTH治疗使未切除和未切除肾上腺的动物阴道开放延迟4天。由于注射ACTH的肾上腺切除大鼠未显示阴道开放延迟，这表明ACTH的抑制作用是由肾上腺介导的。然而，这些动物在第一次发情时出现的卵子数量明显减少，阴道开口时体重明显降低。经acth治疗的完整大鼠阴道开放延迟，孕酮和皮质酮水平升高。在没有表现出性成熟迟缓的动物中，只有皮质酮水平升高。虽然acth治疗大鼠的黄体酮水平长期升高似乎是通过干扰血浆LH来抑制性成熟，但试图显示抑制血浆LH是不成功的。
The effects of ACTH and adrenalectomy on sexual maturation was studied in female rats. Weanling (21-day-old) intact and adrenalectomized female rats received 4 IU/100 gm body weight until Day 40. Animals were sacrificed on Days 25 30 35 40 and on the day of vaginal opening. Blood samples were assayed for progesterone corticosterone luteinizing hormone (LH) and prolactin. Animals sacrificed at 1st estrus were examined for the number of ova present in the Fallopian tubes. ACTH treatment delayed vaginal opening for 4 days in both intact and adrenalectomized animals. Since ACTH-injected adrenalectomized rats did not show a delay in vaginal opening it would appear that the inhibitory effect of ACTH is mediated by the adrenal glands. However these animals had a marked reduction in the number of ova present at 1st estrus and markedly lower body weight at vaginal opening. ACTH-treated intact rats that showed delayed vaginal opening had elevated levels of progesterone and corticosterone. In animals not exhibiting retarded sexual maturation only corticosterone levels were elevated. Although it appeared that the chronically elevated levels of progesterone in ACTH-treated rats inhibited sexual maturation by interfering with plasma LH attempts to show a suppression of plasma LH were unsuccessful.