Hypothalamic control of growth hormone (GH) secretion in type i diabetic men: Effect of the combined administration of gh-releasing hormone and hexarelin, a novel GHRP-6 analog

Insulin dependent (type I) diabetic patients show abnormal growth hormone (GH) secretion. Hexarelin is an analog of GHRP-6 which releases GH in part via somatostatin inhibition. The aim of our study was to evaluate the effects of hexarelin and GHRH, administered either alone or in combination, on GH secretion in 10 type I diabetic and 7 normal men. All the subjects were administered: 1) human GHRH (1-29)NH2 100 μg iv bolus at 0 min; 2) hexarelin 100 μg iv bolus at 0 min; 3) hexarelin 100 μg + hGHRH 100 μg iv bolus at 0 min. In type I diabetic patients significantly greater GH responses to GHRH and hexarelin have been observed with normal subjects. Hexarelin caused a significantly (p