Effects of low dose minocycline on the expression of RGMa in a rat model of middle cerebral artery occlu-sion and reperfusion / 中国神经精神疾病杂志

ABSTRACT

Objective To explore the effects of low dose intravenous minocycline on neurological function and the expression of RGMa in rats after focal cerebral ischemia reperfusion. Methods Fifty-five adult male Sprague-Dawley rats were randomly divided into sham-operated group, cerebral ischemia/reperfusion (I/R) group and minocycline-treat?ed group. The cerebral ischemia/reperfusion model was established by 2 h of middle cerebral artery occlusion. At 2 weeks after ischemia reperfusion, the expression levels of RGMa and growth associated protein 43 (GAP-43) were ana?lyzed by using immunohistochemistry and Western blot, respectively. Neurological functional recovery was evaluated us?ing both the modified neurological severity score (mNSS) and staircase test at 2, 7,14 and 28 d after ischemia reperfusion. Results Minocycline at a dose of 3 mg/kg via the caudal vein significantly reduced the expression of RGMa protein (0.53± 0.08 vs. 1.17±0.15, P<0.05) and enhanced the expression of GAP-43 protein (0.94±0.10 vs. 0.57±0.09, P<0.05) in isch?emic cortex 2 weeks after ischemia reperfusion. Moreover, minocycline could reduce mNSS and improve forelimb motor function when compared to the I/R group (P<0.05). Conclusions Low dose intravenous minocycline (3 mg/kg) can im?prove neurological functional recovery in a rat model of focal cerebral ischemia reperfusion and the mechanism may be re? lated to the down-regulation of RGMa expression and up-regulation of GAP-43 expression.