2.9.1. Acetic acid induced writhing test

The analgesic activity of TIME, TIEAE and TIHE was evaluated using acetic acid induced writhing as previously described. Briefly, acetic acid was administered intraperitoneally (0.7% v/v, 10 ml/kg, b.w.) to the mice to create pain sensibility. Control, standard, TIME-2, TIME-4, TIEAE-2, TIEAE-4, TIHE-2 and TIHE-4 group were administered their individual dose orally 30 min prior to administration of acetic acid solution. Each mouse of all groups was observed individually for counting the number of writhing they made in 15 min commencing just 5 min after the intraperitoneal administration of acetic acid solution. Full writhing was not always accomplished by the animal, because sometimes the animals started to give writhing but they did not complete it. This incomplete writhing was considered as half-writhing and two half-writhing was considered as one full writhing [21]. All data was calculated percent inhibition as follows: