Suppressive effect of tritoqualine on lipid peroxidation and enzyme leakage induced by carbon tetrachloride in rat hepatocytes.

Since tritoqualine (TRQ) is effective in suppressing the increase of serum transaminases in acute hepatic injured rats induced by some hepatotoxins, protection of the hepatocyte membrane is suggested to be one of the pharmacological effects of TRQ. In the present study, we investigated the effects of TRQ on lipid peroxidation and enzyme leakage caused by carbon tetrachloride (CCl4) exposure in isolated hepatocytes and the liver in vivo, compared with vitamin E. The results were as follows: Hepatocytes isolated from TRQ-administered rats showed less enzyme leakage than those from control rats after CCl4 addition. TRQ displayed strong inhibition of lipid peroxidation in isolated hepatocytes. In comparison with vitamin E, TRQ showed almost the same inhibitory action on lipid peroxidation, but a stronger suppression of enzyme leakage. Vitamin E showed a weaker protection from increase of glutamic oxaloacetic transaminase than TRQ, in spite of its stronger inhibition of lipid peroxidation in vivo. From these results, it is suggested that the membrane protecting action of TRQ is partially derived from its suppression of lipid peroxidation, but "another action" may also play an important role in protecting the fragile membrane.