[Effect of protoporphyrin IX on the induction of respiratory impairment of hepatic mitochondria by carbon tetrachloride in rats].

The effect of pretreatment with protoporphyrin IX (PP) on the impairment of hepatic mitochondrial respiration induced by carbon tetrachloride (CCl4) was studied in rats. Treatment of animals intraperitoneally with CCl4 resulted in marked impairment of states 4 and 3 respirations, respiratory control and oxidative phosphorylation of mitochondria in the presence of succinate, beta-hydroxybutyrate or glutamate as substrates. The PP, given intravenously, caused no alterations in those mitochondrial functions. The treatment with PP prior to the administration of CCl4 inhibited the induction of mitochondrial respiratory impairment by CCl4. CCl4 increased markedly the contents of lipid peroxide in the liver but not those in the mitochondria. The increase of hepatic lipid peroxides by CCl4 was markedly reduced by the pretreatment with PP. These results indicate that PP effectively protects the mitochondria from the functional disorder caused by CCl4.