Free fatty acid concentrations and growth hormone secretion in man

Abstract

The relationship between plasma free fatty acid (FFA) concentrations and human growth hormone (HGH) release was investigated in the following manner. FFA concentrations were increased acutely by giving heparin 3 hr after a corn oil meal. When FFA concentrations increased to 2.19 ± 0.28 m M/liter and subsequently decreased to 1.30±0.20 m M/liter, no significant stimulation of HGH release occurred. Elevation of FFA by identical means inhibited maximal HGH concentration achieved after arginine (0.25 g/lb of body weight). When such elevation of FFA concentrations were induced after the ingestion of tenderloin beef, the expected increases in HGH release did not occur. In additional experiments, hyperglycemia and hyperlipemia were achieved by epinephrine infusions, and then arginine was infused. Epinephrine alone did not alter HGH secretion, but HGH responses after arginine were inhibited to the same extent as in experiments in which only FFA was increased.