Activation of Mitochondrial Functions by Malotilate in Relation to Accelerated Liver Regeneration in Partially Hepatectomized Rats

Abstract
Malotilate was orally administered to rats at a dose of 100 mg/kg 2 hr after partial hepatectomy. Mitochondrial state 3 respiration of the liver increased significantly from 23.4 nmol/min/mg protein in the control rats to 29.3 nmol/min/mg protein in the rats administered with malotilate at 3 hr after the hepatectomy (1 hr after the administration). The administration also resulted in higher tendencies in the respiratory control ratio after 3, 6 or 20 hr (1, 4 or 18 hr after the administration) than in the control rats. Although partial hepatectomy made hepatic ATP concentration remarkably low, it gradually increased (from 1.53 .mu.mol/g liver after 3 hr) to a level of 2.03 .mu.mol/g liver after 20 hr in the rats administered with malotilate. No increase in ATP concentration was observed in the control rats. Correspondingly, the adenylate energy charge also showed higher tendencies in the malotilate administered rats. From these results, it is supposed that malotilate activates the mitochondrial functions which results in the increases of ATP concentration and adenylate energy charge. These changes in energy metabolism can be associated with accelerated regeneration of the liver by malotilate.