In the adult male rhesus monkey (Macaca mulatta), unilateral orchidectomy in the face of unchanging gonadotropin stimulation results in partial compensation of testosterone secretion by the remaining testis.
In the adult male rhesus monkey (Macaca mulatta), unilateral orchidectomy in the face of unchanging gonadotropin stimulation results in partial compensation of testosterone secretion by the remaining testis.
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DOI：
10.1210/en.2004-0824
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发表时间：
2004-11
期刊：
影响因子：
4.8
通讯作者：
D. Simorangkir;S. Ramaswamy;G. Marshall;T. Plant
中科院分区：
文献类型：
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作者：
D. Simorangkir;S. Ramaswamy;G. Marshall;T. Plant
本研究在成年猴中检测了促性腺激素非依赖性机制在单侧睾丸切除术（UO）后睾丸睾酮（T）分泌的补偿中所起的作用。我们雇了一个模特（睾丸钳夹），其中用GnRH受体拮抗剂消除内源性促性腺激素分泌，同时用重组人LH和FSH的恒定静脉脉冲输注替代促性腺激素驱动睾丸（每2.5小时1分钟脉冲：LH，0.08-0.12 IU/kg脉冲; FSH，0.12-0.32 IU/kg脉冲），为Leydig细胞提供生理刺激。UO后5 h内（n = 5），循环T浓度下降至UO前水平的43%。然而，到第4天，第一个睾丸的损失得到了部分补偿，这反映在循环T已达到UO前水平的67%的平台，并在研究期间（39天）保持不变。在UO前后的促性腺激素脉冲间期内，T的脉冲模式和衰减难以区分，这一发现表明循环T的恢复是剩余睾丸分泌T增加的结果。有趣的是，在失去第一个睾丸后，剩余睾丸产生的抑制素B也表现出延迟的（尽管是轻微的）补偿（第10-11天为13%; P > 0.05）。这些结果表明，补偿T生产的剩余睾丸后，UO在成年猴中可能实现部分促性腺激素的独立机制，可能涉及到灵长类动物睾丸的直接神经输入。
This study examined, in adult monkeys, the role that gonadotropin-independent mechanisms play in compensation of testosterone (T) secretion by the testis that remains after unilateral orchidectomy (UO). We employed a model (testicular clamp), in which endogenous gonadotropin secretion was abolished with a GnRH receptor antagonist, and the gonadotropin drive to the testes was concomitantly replaced with an invariant iv pulsatile infusion of recombinant human LH and FSH (1-min pulse every 2.5 h: LH, 0.08-0.12 IU/kg.pulse; FSH, 0.12-0.32 IU/kg.pulse) that provided the Leydig cells with a physiological stimulus. Within 5 h of UO (n = 5), circulating T concentrations had declined to 43% of pre-UO levels. By d 4, however, loss of the first testis was partially compensated, as reflected by the finding that circulating T had reached a plateau of 67% of the pre-UO level, where it remained for the duration of the study (39 d). That the recovery in circulating T was the result of increased T secretion by the remaining testis was suggested by the finding that the pulsatile pattern and decay of T during the intergonadotropin pulse interval before and after UO were indistinguishable. Interestingly, inhibin B production by the remaining testis also showed a delayed, albeit, minor, compensation (13% on d 10-11; P > 0.05) after loss of the first testis. These results suggest that compensation in T production by the remaining testis after UO in adult monkeys may be achieved in part by a gonadotropin-independent mechanism that probably involves direct neural inputs to the primate testis.