Wakabayashi I, Kanda M, Miki N, Miyoshi H, Ohmura E, Demura R, Shizume K
Neuroendocrinology. 1980 May;30(5):319-22. doi: 10.1159/000123021.
The present study was conducted to examine roles of brain monoamines and opioid peptides in growth hormone (GH) secretion in unanesthetized, freely behaving rats. The administration of chlorpromazine (CPZ, 300 microgram/100 g, i.v.), an antagonist of brain monoamines, to rats that were passively immunized with antiserum to somatostatin immediately lowered plasma GH levels and inhibited episodic GH secretion. An intraventricular injection of beta-endorphin (3.5 microgram) stimulated GH secretion. This effect was completely inhibited by the prior administration of naloxone (100 microgram/100 g, i.v.), a specific antagonist of opioid peptides, but not by CPZ. In addition, the administration of naloxone did not inhibit episodic GH secretion. The results suggest that CPZ inhibits episodic GH secretion via a factor(s) other than somatostatin. It is also inferred that brain monoamines, but not opioid peptides, play major roles in the regulation of episodic GH secretion in rats.
本研究旨在探讨脑单胺类物质和阿片肽在未麻醉、自由活动大鼠生长激素（GH）分泌中的作用。给被动免疫生长抑素抗血清的大鼠静脉注射脑单胺类物质拮抗剂氯丙嗪（CPZ，300微克/100克），可立即降低血浆GH水平并抑制GH的脉冲式分泌。脑室内注射β-内啡肽（3.5微克）可刺激GH分泌。该作用被阿片肽特异性拮抗剂纳洛酮（100微克/100克，静脉注射）预先给药完全抑制，但未被CPZ抑制。此外，纳洛酮的给药并未抑制GH的脉冲式分泌。结果表明，CPZ通过生长抑素以外的因素抑制GH的脉冲式分泌。还可推断，脑单胺类物质而非阿片肽在大鼠GH脉冲式分泌的调节中起主要作用。
