Changes in expression of GABAAα1 receptors in medial prefrontal cortex in a rat model of neuropathic pain / 中华麻醉学杂志

ABSTRACT

Objective To investigate the changes in the expression of GABAAα1, receptors in medial prefrontal cortex (mPFC) in a rat model of neuropathic pain. Methods Nine male Wistar rats weighing 200-210 g were randomly divided into 3 groups ( n = 3 each) control group (group C) , sham operation group (group S) and neuropathic pain group (group P). Neuropathic pain was induced by chronic constrictive injury. The right sciatic nerve was exposed and 4 loose ligatures were placed on the sciatic nerve at 1 mm intervals with 3-0 chromic catgut. In group S, the right sciatic nerve was exposed but not ligated. The thermal and mechanical pain threshold was measured at 1 d before and 1,4,7, 10 and 14 d after operation. The animals were then sacrificed and the mPFC was removed. The expression of GABAAα1, receptors in mPFC was determined by Western blot. Results Compared with C and S groups, thermal and mechanical pain threshold were significantly decreased and the expression of GABAAα1, receptors was up-regulated in group P ( P ＜ 0.01) . There was no significant difference was in the thermal and mechanical pain threshold and expression of GABAAα1 receptors between C and S groups (P ＞ 0.05). Conclusion Up-regulation of GABAAα1 receptor expression in mPFC may be involved in the development and maintenance of neuropathic pain in rats.