ANTI-NOCICEPTIVE ACTIVITY OF METHANOLIC FRACTION OF ETHANOLIC EXTRACT OF CROCUS SATIVUS STIGMAS IN MICE AND RATS

Background: Extensive use of analgesics like non-steroidal anti-inflammatory drugs, opioid is associated with undesirable side effects often limiting their use. Hence the search for indigenous safer analgesic agent is ongoing. It was considered worthwhile to evaluate analgesic activity of methanolic fraction of ethanolic extract of Crocus sativus (CSEEMF) stigmas. Objective: This study was conducted to evaluate analgesic activity of methanolic fraction of ethanolic extract of Crocus sativus in rats and mice.  Material and method: After obtaining permission from animal ethics committee, the animals were divided into 5 groups of 6 animals each control, standard – Aspirin (75 or 150 mg/kg) or Pentazocine (5 mg/kg), CSEEMF. Antinoceceptive activity of stigmas of CSEEMF was investigated at doses 50 mg/kg, 100 mg/kg and 200 mg/kg through tail-flick method, tail clip method and formalin test in swiss albino mice  and writhing test by using acetic-acid in wistar albino Rats. Results: One-way analysis of variance (ANOVA) followed by Dunnett’s test was applied in the study. Both p<0.05, p<0.001 were considered to be significant. In tail-flick method, CSEEMF produced significant (p<0.05, p<0.001) increase in mean reaction time as compared to control in mice. In tail-clip method, same extract fraction caused significant (p<0.001) inhibition of pain in mice at all the doses. CSEEMF produced statistically significant (p<0.001) reduction in number of writhes induced by acetic-acid in rats. Moreover, there was significant inhibition of pain in both phases of the formalin induced response in mice. Conclusion: Stigmas of Crocus sativus ethanolic extract methanolic fraction exhibited significant central and peripheral analgesic activity.