Fig. 2.

Effect of hop extract on the nociceptive response induced by formalin. Animal were pretreated orally with hop extract (100 mg/kg) for 30 min prior to the formalin (5%, 10 µl) injection subcutaneously into the plantar aspect of the left side hindpaw. The cumulative response time of licking, biting and shaking the injected paw was measured during the period of 0~5 min (1st phase) and 20~40 min (2nd phase). The vertical bars indicate the standard error of the mean. The number of animal used for each group was 8~10 (^***p<0.001, compared with control group).