Hataya Y, Akamizu T, Takaya K, Kanamoto N, Ariyasu H, Saijo M, Moriyama K, Shimatsu A, Kojima M, Kangawa K, Nakao K
Department of Medicine and Clinical Science, Kyoto University Graduate School of Medicine, Kyoto 606-8507, Japan.
J Clin Endocrinol Metab. 2001 Sep;86(9):4552. doi: 10.1210/jcem.86.9.8002.
The synergistic relationship between GH-releasing secretagogue (GHS) and GH-releasing hormone (GHRH) with respect to GH secretion is well known. In the present study, we report a similar relationship between GHRH and ghrelin, a recently identified endogenous ligand for the GHS receptor. In normal male adults, various doses of ghrelin were intravenously administered alone or together with 1.0 microg/kg GHRH. At small doses of 0.08 and 0.2 microg/kg ghrelin, combined administration of the two peptides significantly stimulated GH release in a synergistic manner; the mean GH response values of the two peptide combinations were more than the summed mean GH response values of each peptide alone (P < 0.05). In addition, at 1.0 microg/kg ghrelin, the tendency of the synergistic effect was observed, although the comparison was not statistically significant probably due to a submaximal dose ceiling effect. No synergistic effects with respect to ACTH or prolactin secretion were observed. In conclusion, the synergistic interaction between ghrelin and GHRH was clearly shown and might be useful for a provocation test to diagnose GH deficiency.
生长激素释放促分泌素（GHS）与生长激素释放激素（GHRH）在生长激素分泌方面的协同关系是众所周知的。在本研究中，我们报告了GHRH与胃饥饿素之间的类似关系，胃饥饿素是最近发现的GHS受体的内源性配体。在正常成年男性中，单独或与1.0微克/千克GHRH一起静脉注射不同剂量的胃饥饿素。在0.08和0.2微克/千克的小剂量胃饥饿素时，两种肽联合给药以协同方式显著刺激生长激素释放；两种肽组合的平均生长激素反应值高于每种肽单独的平均生长激素反应值之和（P < 0.05）。此外，在1.0微克/千克胃饥饿素时，观察到协同效应的趋势，尽管由于次最大剂量上限效应，比较无统计学意义。未观察到对促肾上腺皮质激素或催乳素分泌的协同作用。总之，胃饥饿素与GHRH之间的协同相互作用得到了明确显示，可能对诊断生长激素缺乏的激发试验有用。
