Different effects of growth hormone-releasing hormone (GRH) and somatostatin on growth hormone and stable metabolite of prostaglandin E2, 13, 14-dihydro-15-keto-prostaglandin E2 (PGE2-M) in normal subjects.

Twenty four healthy subjects were placed in two treatment groups: 1. The first group consisted of twelve subjects in whom growth releasing hormone (GRH) (1 microgram/kg.BW) resulted in a marked and sustained elevation of serum growth hormone (GH) and a slight and delayed increase in plasma prostaglandin E2-M. In the second group, consisting also of twelve subjects, somatostatin infusion (500 micrograms/250 ml) was initiated and maintained for 60 min. Serum GH significantly decreased at 30 and 60 min during infusion and 15 min thereafter. We did not observe any changes in plasma prostaglandin E2-M during or after somatostatin infusion. The results obtained confirm previous in vitro studies and suggest a possible link between growth releasing hormone and prostaglandin E2 in their action on growth hormone secretion. It seems that somatostatin does not play a role in the control of prostaglandin E2 release.