The influence of ascorbic acid on the hepatic cytochrome P-450, and glutathione in guinea-pigs exposed to 2,4-dichlorophenol.

Chlorophenols, mainly used as biocides, are compounds with a wide spectrum of toxic effects including teratogenic and carcinogenic actions. In this study, the effects of 2,4-dichlorophenol (2,4-DCP) on hepatic microsomal cytochrome P-450, NADPH-cytochrome c reductase activity, liver ascorbic acid (AA) and glutathione (GSH) content were studied in guinea-pigs with a low (2 mg/day/animal) or a high (50 mg/day/animal) ascorbic acid intake. The high AA intake significantly increased liver AA and GSH levels. There was a clear-cut correlation between liver AA and GSH levels. Administration of 2,4-DCP significantly decreased cytochrome P-450 and NADPH-cytochrome c reductase activity in hepatic microsomes isolated from guinea-pigs with the low AA intake. Such a reduction was not observed in intoxicated guinea-pigs with the high AA intake. The results suggest that AA can play a protective role in 2,4-DCP toxicity.