Changes in coenzyme Q level in mitochondria of cirrhotic rat liver.

In the cirrhotic rat liver induced by carbon tetrachloride and phenobarbitone, the concentrations of mitochondrial Coenzyme Q were measured in comparison with other respiratory components. The concentration of cytochrome a(+a3) and Coenzyme Q significantly increased in the cirrhotic liver, without any changes in the ratio of Coenzyme Q to cytochrome a(+a3). It is suggested that such increase of Coenzyme Q plays an important role as one of the adaptive responses to compensate for the prolonged metabolic overload on the mitochondrial respiratory assembly. Also, from the findings that the concentrations of cytochrome a(+a3) in the mitochondria of cirrhotic liver increase concomitant with the severity of cirrhosis, it is suggested that the rise of Coenzyme Q levels may be one of the indicators for the decreased functional reserve capacity in liver cirrhosis.