Role of microglial activation in dorsal root ganglia in a rat model of persistent postoperative pain evoked by skin/muscle incision and retraction / 中华麻醉学杂志

ABSTRACT

Objective To evaluate the role of microglial activation in dorsal root ganglia in a rat model of persistent postoperative pain evoked by skin/muscle incision and retraction (SMIR).Methods Seventy male Sprague-Dawley rats,weighing 200-250 g,were randomly divided into 2 groups (n =35 each)group sham operation (group S) and group SMIR.The rat model of persistent postoperative pain evoked by SMIR was established according to the method described by Flatters.Pain behavior was assessed by mechanical paw withdrawal threshold to yon Frey filament stimulation at 1 day before and 1,3,7,12,22 and 32 days after operation.Five animals were sacrificed at each time point in each group for microglia count in dorsal root ganglia.Results Compared with group S,mechanical paw withdrawal threshold was significantly decreased at 3-22 days after operation,and microglia count was significantly increased at 3-12 days after operation in group SMIR (P ＜ 0.05).Conclusion Microglial activation in dorsal root ganglia may be involved in the development of SMIR-evoked persistent postoperative pain in rats.