The hepatoprotective activity of aqueous-methanolic extract of Cyperus scariosus (Cyperaceae) was investigated against acetaminophen and CCl4-induced hepatic damage. 2. Acetaminophen produced 100% mortality at a dose of 1 g/kg in mice while pretreatment of animals with plant extract (500 mg/kg) reduced the death rate to 30%. 3. Acetaminophen at a dose of 640 mg/kg produced liver damage in rats as manifested by the rise in serum levels of alkaline phosphatase (ALP), glutamate oxaloacetate transaminase (GOT) and glutamate pyruvate transaminase (GPT) to 430 +/- 68, 867 +/- 305 and 732 +/- 212 IU/l (n = 10) respectively, compared to respective control values of 202 +/- 36, 59 +/- 14 and 38 +/- 7. 4. Pretreatment of rats with plant extract (500 mg/kg) significantly lowered (P < 0.05) the respective serum ALP; GOT and GPT levels to 192 +/- 31, 63 +/- 9 and 35 +/- 8. 5. The hepatotoxic dose of CCl4 (1.5 ml/kg; orally) raised serum ALP, GOT and GPT levels to 328 +/- 30, 493 +/- 102 and 357 +/- 109 IU/l (n = 10) respectively, compared to respective control values of 177 +/- 21, 106 +/- 15 and 47 +/- 12. 6. The same dose of plant extract (500 mg/kg) was able to significantly prevent (P < 0.05) CCl4-induced rise in serum enzymes and the estimated values of ALP, GOT and GPT were 220 +/- 30, 207 +/- 95 and 75 +/- 38, respectively. 7. The plant extract also prevented CCl4-induced prolongation in pentobarbital sleeping time confirming hepatoprotectivity.(ABSTRACT TRUNCATED AT 250 WORDS)
