Chronic Ethanol Ingestion and Glycogen Metabolism in Male and Female Rats

Abstract

Both acute (Nelson et al., 1969) and chronic (Walker and Gordon, 1970) ethanol ingestion induces marked depletion of liver glycogen in males. This is important in view of the fact that increased glycogen breakdown results in inadequate carbohydrate stores, and inadequate carbohydrate stores may be a predisposition that leads to hypoglycemia following ethanol ingestion (Freinkel et al., 1963). With the exception of one abstract, which reported a 54% increase in phosphorylase activity (Williams, 1965), no definitive study of the effects of ethanol ingestion on the enzymes of glycogen metabolism has been reported. Because phosphorylase a is thought to be the primary regulator of both the nreakdown and synthesis of liver glycogen (Hers, 1976), it is important to understand how ethanol affects its activity. Glucose enhances the inactivation of hepatic phosphorylase a (Stalmans et al., 1970); therefore, blood glucose levels also are important in the control of glycogen metabolism.