Tryptophan potentiation of the late cysteine preventive effects in carbon tetrachloride-induced necrosis.

Carbon tetrachloride (CCl4) (1 ml/kg/ip) induces a very intense necrotic effect on rat liver at 24 hr after administration. Cysteine (950 mg/kg/po) given 6 h after CCl4 exerted a very weak preventive effect on CCl4-induced necrosis, while tryptophan (300 mg/kg/po) did not. When both aminoacids are given together a very marked protective effect is observed. A possible participation of protein synthesis stimulation in the late protective effects of cysteine on CCl4-induced liver necrosis is discussed.