Prevention of barbiturate-mediated increases of rat hepatic ornithine decarboxylase and δ-aminolevulinic acid synthetase activities by nicotinic acid and nicotinamide

Abstract

Administration of secobarbital to rats produced dramatic increases in the activities of hepatic ornithine decarboxylase and δ-aminolevulinic acid synthetase at three hours which were reversed by administration of either nicotinic acid or nicotinamide. No appreciable alterations of the activity of either enzyme were observed following administration of nicotinic acid. Administration of nicotinamide produced a significant increase of ornithine decarboxylase activity, but failed to alter the activity of δ-aminolevulinic acid synthetase.