Evaluation of the analgesic effect of the extract from Coptosapelta flavescens Korth. stem on white mice

Abstract

   Cao Khai (The extract from Coptosapelta flavescens Korth. stem) is a traditional remedy in treatment of pain, inflammation… In the present study, we investigated the analgesic effect of Cao Khai. Peripheral analgesic activity test used acetic acid-induced writhing model on mice by counting the number of writhes and the total time of writhes every 5 minutes in 40 minutes after the injection. Central antinociceptive activity was evaluated with the tail-flick method in which the tail is immersed in hot water at (52 ± 0,5) ⁰C. The latency time were measured at (60, 90, 120 and 150) minutes. Diclofenac and morphine were used as a control in these experiments. Cao Khai 400 mg/kg has not shown the effect on peripheral analgesic and central analgesic (p > 0.05). Cao Khai 800 mg/kg exhibits peripheral analgesic effect by reducing the number of writhes (0 ¸ 30) min and the total time of writhes (0 ¸ 35) min (p < 0.05). In the central analgesic experiment, Cao Khai 800 mg/kg increased the latency time to 150 minutes (p < 0.05).