The central analgesic and anti-inflammatory activities of the methanolic extract of Carthamus oxycantha

The plant extract and fractions of carthamus oxycantha (compositae) were assessed for analgesic and anti-inflammatory activities. acetic acid and formalin-induced nociception,hot plate and carrageenan-induced rat paw oedema tests were employed to evaluate the analgesic and anti-inflammatory potential of the plant extract. the intraperitoneal (i.p.) administration of the methanolic extract (25-30 mg/kg),hexane (10-50 mg/kg,i.p.) and ethylacetate (50 and 100 mg/kg i.p.) fractions produced significant inhibition (p<0.01) of the acetic acid-induced writhing in mice and suppressed formalin-induced licking response of animals in both phases of the test. in the hot plate assay the plant extract (100 mg/kg i.p.) increased pain threshold of mice. pre-treatment of animals with naloxone (5 mg/kg i.p.) abolished the analgesic effect of the c. oxycantha in formalin and hot plate tests. c. oxycantha (50-200 mg/kg i.p.) produced marked anti-inflammatory effect in carrageenan-induced rat paw edema assay comparable to diclofenac. these findings suggest that c. oxycantha possesses central analgesic and peripheral anti-inflammatory properties,with analgesic effects associated with the opioid system.