Role of prostaglandin E2 (PGE2) in the growth hormone releasing hormone action on growth hormone, insulin and C-peptide in normal men.

Fourteen healthy men were placed in two treatment groups. 1. Seven men received growth releasing hormone (1 microgram/kg BW) intravenously during either saline or prostaglandin E2 (10 micrograms/min) infusion which were started 60 minutes before testing. Growth hormone response to growth releasing hormone was greater during prostaglandin E2 infusion compared to the control study. These data suggest that exogenous prostaglandin E2 positively modulates growth hormone response to growth releasing hormone. In the second group consisting also of 7 men a GRH test was performed before and after 3 days administration of meclofenamate. Meclofenamate significantly reduced plasma levels of stable metabolites of prostaglandin E2 as well as the growth hormone to growth releasing hormone, suggesting that the GRH effect on GH was at least partly under prostaglandin E2 control. GRH significantly reduced serum insulin in the two treatment groups. PGE2 infusion or meclofenamate did not change insulin response to GRH. Serum C-peptide and blood glucose did not change after GRH injection during saline or PGE2 infusions.