Toxicology Letters, 24 (1985) 53-58 Eisevier 53 TOXLett. 1339 QUINURONIUM INDUCED HEPATOTOXICITY IN RATS (Quinuronium; hepatotoxicity; rats) E.S. MITEMA and J.M. MARIBEI* Department of Public Heairh, Pharmacolog>~ and Toxicology and *Department of Cbnical Studies, Faculty of‘ Yeterinary medicine, P.O. Box 29053, Nairobi (Kenya) (Received October lst, 1984) (Accepted October Sth, 1984) SUMMARY Two groups of 6 rats each received subcutaneous injections of 2.3 mg/kg or 5.0 mg/kg of quinuronium, respectively, on two consecutive days, while 5 rats injected with physiological saline served as controls. Clinical signs of muscular tremors, jumps, enlarged and hyperemic eyeballs, lacrimation, depression and anorexia were observed following administration of quinuronium. One rat receiving 5 mg/kg died before termination of the study. When killed 48 h after the first injection, the quinuronium- treated rats had a higher liver weight/body weight ratio compared to the controls. Quinuronium resulted in hepatic centrilobular fatty degeneration, but no depletion of hepatic glutathione (GSH). The present findings suggest that glutathione depletion does not seem to be involved in quinuronium hepatotoxicity. INTRODUCTION Quinuronium sulfate has been used in the treatment of babesiosis of domestic animals for many years. Naude et al. [l] and Homeida et al. [2] reported hepatic dysfunction in dogs and camels, respectively, administered quinuronium. Recent in- vestigations have also demonstrated that quinuronium affects liver biochemical parameters in cattle [3] and rats [4]. The present study has been undertaken as an extension of earlier studies to in- vestigate hepatic histopathological changes, liver weight/body weight ratios and possible depletion of hepatic GSH due to inactivation of reactive metaboIites. MATERIALS AND METHODS Animals and drug treatments Male albino rats (Veterinary Laboratories, Kabete, Kenya), approx. 200 g, were Abbreviations: GSH, glutathione; PBS, phosphate-buffered saline; TCA, trichloroacetic acid. 0378-4274/85/S 03.30 0 Elsevier Science Publishers B.V.