A modified method for evaluating analgesic activity of drugs using Rana tigrina frog

Background: Different species of frogs had been used by many researchers for evaluation of analgesic drugs e.g., Rana pipiens and African claw frog. In our study, we used Rana tigrina, which was never used for evaluation of analgesic activity of drugs. So by doing this project, we judged usefulness of R. tigrina to evaluate analgesic drugs. Methods: Animals used were R. tigrina of either sex weighing 100-150 g. Glass flask with porous platform was used for observation of frog. All groups were treated with 4% NaCl solution S.C. on abdomen). Characteristic parameter i.e., number of eye blinkings (this parameter was observed during the pilot study after 4% NaCl S.C. injection on lower third of frogs abdominal wall) were observed before and after drug administration. Each observation was for 5 mins. Centrally and periphrally acting drugs effect was tested on the number of blinks and buccal oscillations. Results: Centrally acting drug inhibit rise in number of eye blinkings and buccal oscillation significantly. Piroxicam diclofenac sodium and ketoprofen decreased rise in number of blinks; but, it was not significant as compared with control. Conclusion: This animal may be used alternative to existing methods of evaluating analgesics in Indian setup.