Pyruvate kinase isozymes: A comparative study in tissues of various mammalian species

Abstract

1. 1. Pyruvate kinase activity and electrophoretic patterns of pyruvate kinase isozymes of liver, kidney, heart and skeletal muscle were compared in male adult rats, hamsters, guinea pigs, rabbits, cats, dogs, monkeys and a human. Liver pyruvate kinase isozymes were separated and quantitated by DEAE-cellulose chromatography. 2. 2. Significant species differences in total pyruvate kinase activity occurred in all tissues but especially in the liver and skeletal muscle. 3. 3. Two electrophoretic distinct forms of pyruvate kinase were observed in the liver; one, four or five forms in the kidney; and one form in the heart and skeletal muscle of the species studied. 4. 4. DEAE-cellulose chromatography gave a quantitative recovery of two liver isozymes. Pyruvate kinase isozyme 1 predominated in most species. Only in the cat and human were liver isozymic activities about equally distributed between the two forms.