The effect of chronic ethanol ingestion on myocardial glucose and energy metabolism

To determine the effect of chronic alcohol ingestion, rats were given 15 or 25% v/v of alcohol in water for a period of 6 months. The activities of some key enzymes involved in the metabolism of glucose, mitochondrial respiratory rates, and efficiency of oxidative phosphorylation were studied in the hearts of alcohol-treated and untreated rats. In the group receiving 15% alcohol, glucose-6-phosphate dehydrogenase (G-6-PDH) was elevated. In rats given 25% alcohol, activities of G-6-PDH, aldolase, and glyceraldehyde phosphate dehydrogenase were elevated but isocitrate dehydrogenase was reduced. Mitochondrial respiratory rates and the efficiency of phosphorylation were depressed in rats given 25% of alcohol. Except for mitochondrial oxidation of pyruvate and alpha-ketoglutarate, all biochemical parameters studied were within normal limits a month after alcohol was discontinued.