Hyperglucagonemia in liver cirrhosis with portal-systemic venous anastomoses: responses of plasma glucagon and gastric inhibitory polypeptide to oral or intravenous glucose in cirrhotics with normal or elevated fasting plasma glucose levels.

Plasma immunoreactive glucagon (IRG) was examined in volunteers with biopsy-proven cirrhosis of the liver after recovery from surgical portal--caval anastomosis. A wide range of increased total plasma IRG concentrations was found after overnight fast in groups of cirrhotic subjects with and without fasting hyperglycemia. Gel filtration chromatography of plasma showed a major component in the 3500-mol wt fraction in all cases so studied. Administration of glucose i.v. caused rapid suppression of total plasma IRG in normoglycemic and non-insulin-dependent hyperglycemic cirrhotic subjects. After administration of oral glucose, total plasma IRG was suppressed rapidly in normoglycemic cirrhotic subjects, while non-insulin-dependent hyperglycemic cirrhotic subjects exhibited delayed but prolonged suppression. Chromatography of selected plasma with glucose-suppressed total IRG showed a major decrease in the 3500-mol wt component in every case. Exaggerated increments of plasma gastric inhibitory polypeptide were demonstrable in both groups of cirrhotic individuals after administration of oral glucose, and it is speculated that this peptide may contribute to stimulation of glucagon secretion in liver disease associated with insulin deficiency.