Role of food intake in the modulation of hexarelin-induced growth hormone release in normal human subjects

Hexarelin (HEX) is a new synthetic analog of the Growth Hormone releasing peptides and is stronger than GHRH in releasing GH in vivo. No information is available on the effect of food ingestion on HEX-induced GH secretion. On the other hand, we have previously demonstrated that food intake at lunchtime in normal subjects has an inhibitory effect on the GH response to GHRH. The aim of the present study was to investigate the effect of food ingestion on GH secretion induced by HEX as compared to GHRH in six normal men (aged 23-29 years) and six normal women (aged 24-29 years). The body weights for all subjects were within 120% of their ideal body weight, according to their sex and age. Our data confirm that HEX is much more powerful than GHRH in inducing GH release in humans, both in the fasting state (GH-AUC: 3010 +/- 695 after HEX, vs. 1339 +/- 281 after GHRH, microg/L/120 min; p