Analgesic effect of morphine combined with lornoxicam in different proportions on incision pain in rat / 解放军医学杂志

ABSTRACT

Objective To compare the analgesic effect of morphine combined with lornoxicam in different proportions in rats. Methods 63 male adult SD rats were assigned randomly into nine groups (7 each). Under the 1.4% isoflurane anesthesia, an incision of 1cm in length was made in the plantar region of the left hind paw parallel to the muscle according to the method of Brennan. The rats in sham operation group (A) inhaled 1.4% isoflurane for 5 min but no incision was made, the rats in operation control group (B) received hypodermic injection of 1ml 0.9% NaCl 1h after incision, the rats in groups C to H and group L received hypodermic injection of morphine combined with lornoxicam in different proportions (6mg/kg∶0mg/kg; 1mg/kg∶5mg/kg; 2mg/kg∶4mg/kg; 3mg/kg∶3mg/kg; 4mg/kg∶2mg/kg; 5mg/kg∶1mg/kg and 0mg/kg∶6mg/kg, respectively) 1h after incision. Analgesic effect was assessed by cumulative pain score within 1 hour after administration. Results The cumulative pain scores of rats in group A was 0.375?0.518, which was significantly lower than that of the other groups (P0.05). The scores in groups F and G were 3.625?1.061 and 3.750?1.165 respectively, which were significantly lower than those in groups C, D, E and L (P