Acute effects of oral and intravenous ethanol on rat hepatic enzyme activities

Abstract

1. 1. Oral administration of ethanol (3 ml) of 95% in 12 ml total volume over a two day period) significantly decrease plasma glucose and insulin levels and the activities of two key gluconeogenic enzymes, pyruvate carboxylase (pyruvate: CO 2 ligase (ADP), EC 6.4.1.1) and fructose diphosphatase, ( d-Fru -1,6-P 2 1-phosphohydrolase, EC 3.1.3.11), and one glycolytic enzyme, fructose-1,6- P 2 aldolase ( Fru-1,6-P 2 d-glyceraldehyde -3-P lyase , EC 4.1.2.13). In each instance, the administration of 2400 μg daily of oral folate in conjunction with the ethanol prevented these alterations in carbohydrate metabolism. 2. 2. Intravenous injection of ethanol produced a rapid decrease (within 10–15 min) in the activities of hepatic phosphofructokinase, (ATP: d-fructose-6-phosphate 6-phosphotransferase, EC 2.7.1.11), pyruvate kinase, (ATP: pyruvate phosphotransferase, EC 2.7.1.40), fructose diphosphatase and fructose-1,6- P 2 aldolase. 3. 3. Intravenous ethanol significantly increased hepatic cyclic AMP concentration approximately 60% within 10 min, while oral ethanol did not alter hepatic cyclic AMP concentrations. 4. 4. These data confirm the known antagonism ethanol and folate and suggest that oral folate might offer a protective effect against hypoglycemia in rats receiving ethanol.