Fanciulli G, Oliva O, Tomasi P A, Pala A, Bertoncelli A, Dettori A, Delitala G
Chair of Endocrinology, University of Sassari, Italy.
Eur J Endocrinol. 1996 Jan;134(1):73-6. doi: 10.1530/eje.0.1340073.
Exogenous growth hormone (hGH) administration in humans attenuates the endogenous growth hormone (GH) response to some pharmacological stimuli; in particular, pretreatment with hGH completely blocks the serum GH response to growth hormone-releasing hormone. In order to evaluate the mechanism(s) whereby opiods induce GH secretion in man, we gave the following treatments to six healthy male volunteers: (a) IV saline; (b) a met-enkephalin analog G-DAMME 250 micrograms IV as a bolus at time 0'; (c) hGH 2 IU as an IV bolus at time -180'; (d) G-DAMME as above, preceded by hGH as above. In our study, G-DAMME stimulated GH secretion both basally (peak 17.9 +/- 6.0 ng/ml) and, to a lesser extent, after hGH pretreatment (6.0 +/- 2.7 ng/ml). Since in our study G-DAMME was able to partially overcome the inhibitory effect of hGH administration, it is suggested that opioids act through an inhibition of somatostatin release and not through a GHRH-dependent pathway. However, an additional direct effect of hGH on pituitary somatotrophes cannot be excluded.
在人类中给予外源性生长激素（hGH）会减弱内源性生长激素（GH）对某些药理刺激的反应；特别是，用hGH预处理会完全阻断血清GH对生长激素释放激素的反应。为了评估阿片类药物在人体内诱导GH分泌的机制，我们对六名健康男性志愿者进行了以下治疗：（a）静脉注射生理盐水；（b）在0分钟时静脉推注250微克甲硫氨酸脑啡肽类似物G-DAMME；（c）在-180分钟时静脉推注2国际单位hGH；（d）先按上述方法给予hGH，再按上述方法给予G-DAMME。在我们的研究中，G-DAMME在基础状态下（峰值为17.9±6.0纳克/毫升）以及在hGH预处理后（6.0±2.7纳克/毫升）均能刺激GH分泌，不过刺激程度较小。由于在我们的研究中G-DAMME能够部分克服给予hGH的抑制作用，提示阿片类药物是通过抑制生长抑素释放起作用，而非通过生长激素释放激素（GHRH）依赖途径。然而，不能排除hGH对垂体生长激素细胞的额外直接作用。
