Mann D R, Davis-DaSilva M, Wallen K, Coan P, Evans D E, Collins D C
J Clin Endocrinol Metab. 1984 Aug;59(2):207-11. doi: 10.1210/jcem-59-2-207.
The objective of this study was to determine the effects of continuous GnRH agonist (Ag) treatment on neonatal activation of the pituitary-testicular axis in male rhesus monkeys. Five infants were treated continuously with Ag(10 micrograms/day; Wy-40972) for 112 days using osmotic minipumps beginning at 10-13 days of age. Two of five age-matched control animals were implanted sc with Silastic implants of comparable size to the minipumps; three did not receive sham implants. Ag treatment caused a fall in serum LH (bioassay) values to undetectable levels (much less than 0.1 micrograms/ml) within 3 weeks, where they remained throughout Ag treatment. Mean serum testosterone (T) levels fell from pretreatment values of 1.52 +/- 0.45 to 0.38 +/- 0.09 (+/- SE) ng/ml after 3 weeks of Ag treatment. The level of T never exceeded 0.60 ng/ml throughout the subsequent course of Ag treatment. In contrast, serum LH and T were elevated to levels that approached adult values during the first 2 postnatal months in control infants with or without sham implants. Both LH and T then gradually declined, and by 4 months of age, T levels were indistinguishable from those in Ag-treated animals. Control infants had an increase in serum LH from 0.56 +/- 0.10 to 2.67 +/- 0.49 micrograms/ml within 60 min of administration of 5 micrograms GnRH/kg BW at 60 days of age. Serum T values rose from 2.35 +/- 1.00 to 9.48 +/- 3.15 ng/ml during the same period. Seven weeks of Ag treatment abolished the LH and T responses to GnRH. Thirty days after the termination of Ag treatment (approximately 150 days of age), Ag-treated and control infants had comparable serum LH and T responses to GnRH, although the responses were reduced relative to the responses in controls at 60 days of age. These results suggest that continuous administration of Ag desensitizes the pituitary of the male infant rhesus monkey to GnRH and blocks neonatal activation of the pituitary-testicular axis.
本研究的目的是确定连续给予促性腺激素释放激素（GnRH）激动剂（Ag）对雄性恒河猴垂体 - 睾丸轴新生儿期激活的影响。5只幼猴从10 - 13日龄开始使用渗透微型泵连续112天接受Ag（10微克/天；Wy - 40972）治疗。5只年龄匹配的对照动物中有2只皮下植入了与微型泵大小相当的硅橡胶植入物；3只未接受假植入。Ag治疗使血清促黄体生成素（LH，生物测定法）值在3周内降至检测不到的水平（远低于0.1微克/毫升），在整个Ag治疗期间一直保持在该水平。Ag治疗3周后，血清睾酮（T）平均水平从治疗前的1.52±0.45降至0.38±0.09（±标准误）纳克/毫升。在随后的Ag治疗过程中，T水平从未超过0.60纳克/毫升。相比之下，无论有无假植入，对照幼猴在出生后的前2个月内血清LH和T升高至接近成年值的水平。随后LH和T均逐渐下降，到4月龄时，T水平与接受Ag治疗的动物无法区分。60日龄的对照幼猴在静脉注射5微克GnRH/千克体重后60分钟内，血清LH从0.56±0.10升高至2.67±0.49微克/毫升。同期血清T值从2.35±1.00升高至9.48±3.
