Corticotrophin-releasing hormone does not inhibit growth hormone-releasing hormone-induced release of growth hormone in control subjects but is effective in patients with eating disorders

Abstract

Previous studies have shown that corticotrophin-releasing hormone (CRH) inhibits GH secretion in response to GH-releasing hormone (GHRH) in normal women and men, and animal studies suggest that this effect is mediated by an increased release of somatostatin from the hypothalamus. It has been reported that there are abnormalities in the neuroendocrine regulation of the hypothalamo-pituitary-somatotrophic axis and the hypothalamo-pituitary-adrenocortical axis in patients with eating disorders. The present study therefore investigated the ability of CRH to inhibit the GH response to GHRH in eight young women with anorexia nervosa (AN) and in seven young women with eating disorders which were not otherwise specified (NOS). We also compared the effect of CRH in the patients with the response it caused in ten control women. In contrast to a previous report, combined i.v. administration of 50 micrograms human CRH (hCRH) and 50 micrograms GHRH(1-29) caused a GH response in control women which was higher, although not significantly so, than that induced by GHRH alone (area under the curve (AUC) 988.5 +/- 506.0 compared with 1568.4 +/- 795.6 (S.E.M.) ng/ml per 120 min for GHRH alone and GHRH plus hCRH respectively). Conversely, the administration of hCRH given together with GHRH markedly inhibited the GH response induced by the latter in both AN patients (AUC 2253.0 +/- 385.7 compared with 1224.4 +/- 265.7 ng/ml per 120 min for GHRH and GHRH plus hCRH respectively; P < 0.005 and NOS patients (AUC 2827.4 +/- 281.1 compared with 308.5 +/- 183.4 ng/ml per 120 min for GHRH and GHRH plus hCRH respectively; P < 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)

Direct effects of corticotrophin-releasing hormone on stimulated growth hormone secretion

“…This study confirms that, in man, pretreatment with an intravenous bolus of CRH(1-41) leads to a significant reduction in the serum GH response to GHRH-(1-29)-NH 2 . These results are in agreement with earlier reports (Holsboer et al, 1988;Barbarino et al, 1990;Ghizzoni et al, 1996), although others have failed to document this effect (Hartog et al, 1964;Looij et al, 1986;Rolla et al, 1994). The discrepancy in the findings reported by Looij et al (1986) and our own may reflect the lower dose of CRH used (50 mg), although this was sufficient to inhibit the noctural surge of GH in the study by Holsboer et al (1988).…”

Effect of galanin on basal and stimulated secretion of prolactin, gonadotropins, thyrotropin, adrenocorticotropin and cortisol in humans

“…In fact, both in animals (39) and in man (23), CRH has been reported to inhibit the GH response to GHRH. However, other authors failed to find any inhibitory effect by CRH on GHRH-induced GH release in man (40). Our present results show that CRH does not influence the GH response to galanin.…”

Hexarelin, a Synthetic Growth-Hormone Releasing Peptide, Shows No Interaction with Corticotropin-Releasing Hormone and Vasopressin on Adrenocorticotropin and Cortisol Secretion in Humans

“…Particularly, the lack of any effect of hCRH on the HEX-induced GH rise agrees with other data showing that the somatotrope response to GHRH is not modified by hCRH co-administration in normal young volunteers [34], though an inhibitory effect of hCRH on the GHRH-induced GH response had pre viously been reported [35].…”