Alterations of Pyruvate Kinase Isozyme Activities in Experimental Liver Injuries in Rat and Their Pathophysiological Significance

• Published in: Kanzo Vol. 17; no. 4; pp. 240 - 255
• Main Author: TAKESUE, Atsushi
• Format: Journal Article
• Language: Japanese
• Published: The Japan Society of Hepatology 1976
• Subjects: pyruvate kinase isozyme; translation
• ISSN: 0451-4203; 1881-3593
• DOI: 10.2957/kanzo.17.240

Activities of pyruvate kinase isozymes, PK-L and PK-M2, in rat liver were determined either by differential inhibition by ATP in the presence of high concentration of MgCl2 or Cellogel electrophoresis and densitmetry. In experimental liver injuries, such as acute intoxications with CCl4, thioacetamide, D-galactosamine or allyl formate, a chronic intoxication with CCl4 and a feeding on a choline deficient diet, PK-L activity was reduced to half, while PK-M2 activity increased 10 folds. The elevation of PK-M2 activity in CCl2-injured liver was based on de novo synthesis of PK-M2 independent of de novo synthesis of RNA and DNA. The pathophysiological significance of the altered PK isozyme pattern in acute liver injury appears to represent a positive responce to the toxic stimulus, directed toward the survival and repair of the injured hepatic cells.