EFFECTS OF CHLOROQUINE TREATMENT ON ANTIOXIDANT ENZYMES IN RAT-LIVER AND KIDNEY

The effect of chloroquine (CHQ) administration on antioxidant enzymes in rat Liver and kidney was studied. Male Sprague-Dawley rats were adm inistered 20 mg/kg CHQ once a week for 4 weeks (chronic treatment) or a single dose at 10 or 20 mg/kg (acute treatment). Antioxidant enzyme activities were determined in cytosolic fractions of liver and kidney, whereas reduced glutathione (GSH) and malondialdehyde (MDA) were dete rmined in tissue samples. Results indicate minimal effects of acute CH Q treatment, whereas chronic treatment with CHQ differentially affecte d antioxidant enzymes in the two organs. Superoxide dismutase activity was increased nearly twofold, while activities of selenium glutathion e peroxidase (GPX), catalase, and NAD (P) H: quinone oxidoreductase we re decreased in livers of CHQ-treated rats compared to controls. No si gnificant effects of CHQ on glutathione reductase, GSH, and MDA levels were seen in the liver. Fewer effects of CHQ were observed in the kid ney where a decrease in GPX activity and an increase in MDA levels was seen. Lowering of antioxidant enzymes activities in the liver by CHQ could render the organ more susceptible to subsequent oxidative stress ; while increased MDA production after CHQ treatment in the kidney ind icate that the organ is being subjected to oxidative stress. This coul d have implications for prolonged chloroquine intake. Copyright (C) 19 96 Elsevier Science Inc.