Hepatic glycogenolysis induced by glucagon in a patient with type I liver glycogen disease

Abstract

Direct evidence was obtained, by chemical and isotopic measurements, that glucagon induces active hepatic glycogenolysis in type I liver glycogen disease, at a rate comparable to that observed in normal rats and dogs and, presumably, normal man. This liver glycogen breakdown was associated with no increase in blood glucose, but in a rapid rise of blood lactate. Indirect evidence suggests that the response to endogenous secretion of glucagon is similar. The conclusion that both exogenous and endogenous glucagon exert their usual glycogenolytic effects in this disease but that the end product is lactic acid rather than glucose indicates that (1) the abnormal accumulation of liver glycogen observed in type I glycogen disease is not a consequence of the deficiency in glucose-6-phosphatase per se (2) increased glycogen synthesis must play a major role in accounting for this excessive liver glycogen content.