CHROMIUM (III) DECREASES CARBON TETRACHLORIDE-ORIGINATED TRICHLOROMETHYL RADICAL IN MICE

Effects of the administration of trivalent chromium (Cr(III)) to mice and the activation of carbon tetrachloride (CCl4) to form trichloromethyl radicals (.CCl3) in the liver were studied. The lipid peroxidation in liver microsomes induced in vitro by CCl4 in the presence of NADPH was decreased by the preadministration of Cr(III) to mice. The activity of NADPH-cytochrome C reductase, which presumably catalyzes the formation of .CCl3 from CCl4 in liver microsomes, was depressed by Cr(III) administration and kept at a level lower than that of the control group for at least 2 hr after CCl4 dosing. Furthermore, the frequency of appearances of ESR signals of .CCl3 in the liver homogenate of mice 1 min after CCl4 administration was markedly decreased by Cr(III) preadministration, similarly to DL-alpha-tocopherol. These results suggest that Cr(III) preadministered to mice decreases the formation of .CCl3 from CCl4, an activating process of CCl4, in the liver, presumably by scavenging the radical.