The Effect of Lobeline on the Analgesia by Ketamine

Objective: To observe the effect of lobe line on the analgesia by ketamine. Methods: 80 mice were randomly divided into 2 large groups (hotwater tail-flick group and writhing group) ,each of which was further divided into 4 groups with 10 mice in each group: NS plus ketamine group (KN group) ,1 mg/kg lobeline plus ketamine group (KL1 group) ,2 mg/kg lobeline plus ketamine group(KL2 group) ,3 mg/kg lobeline plus ketamine group(KL3 group) . Using tail-flick test and writhing test,the effect of lobeline at different concentrations on the analgesic action of ketamine was observed. Results: The injection of lobeline(1,2 and 3 mg/kg) decreased the HPPT of the mice after injection of ketamine (P 0. 05) . The injection of lobeline(2 and 3 mg/kg) obviously increased writhing times of the mice after injection of ketamine (P 0. 01) . But the injection of lobeline (1 mg/kg) had no obvious effect on the writhing times of the mice after injection of ketamine. Conclusions: Lobeline(1 ～ 3 mg/kg) can antagonize the the analgesia by ketamine.