Effect of lipids on glucagon secretion in man

Abstract

Animal experiments have suggested a FFA control mechanism for glucagon secretion. In man, the potent effect of FFA on HGH secretion and the similarity of the secretory control mechanisms for HGH and IRG also support a role of FFA in IRG secretion. Our studies in man in which plasma FFA were elevated by either an oral lipid emulsion (Lipomul) or an intravenous lipid suspension (Intralipid) suggest only a minor role of lipids in control of IRG secretion. Plasma FFA and triglyceride elevations did not suppress arginine- or hypoglycemia-induced plasma IRG elevations, but an inhibitory effect of Intralipid on basal plasma IRG concentrations was observed. Although nicotinic acid administration, which caused a depression in plasma FFA, did elevate plasma IRG, the IRG elevation was considered more likely a consequence of stress induced by the drug. The failure of lipids to inhibit IRG secretion at FFA concentrations inhibiting HGH secretion indicates a dissociation in the secretory control mechanisms of the two hormones.