【摘要】 探探讨肢体缺血预处理(limb ischemic preconditioning,LIP)对大鼠全脑缺血再灌注后海马CA1区锥体细胞凋亡的影响。46只大鼠椎动脉凝闭后分为假手术组、肢体缺血组、脑缺血组、LIP组。重复夹闭大鼠双侧股动脉3次(每次10min,间隔10min)作为LIP,之后立即夹闭双侧颈总动脉进行全脑缺血8min后再灌注。DNA凝胶电泳、TUNEL和吖啶橙/溴乙锭(AO/EB)双染技术从生化和形态学方面观察海马神经元凋亡的情况。凝胶电泳显示,脑缺血组出现了凋亡特征性DNA梯状条带,而LIP组无上述条带出现。与脑缺血组比较,LIP可明显减少海马CAI区TUNEL阳性神经元数(17.8±5.8vs 69.8±12,P<0.01)。AO/EB染色也显示LIP可明显减少脑缺血再灌注引起的神经元凋亡。以上结果提示,LIP可抑制脑缺血再灌注后海马神经元的凋亡,进而减轻脑缺血再灌注损伤,提供脑保护作用。更多还原

【Abstract】 The purpose of this study was to investigate the effects of limb ischemic preconditioning (LIP on apoptosis of pyramidal neuronsin the CA1 hippocampus induced by global cerebral ischemia-reperfusion in rats. Forty-six rats whose bilateral vertebral arteries were occludedpermanently were assigned to one of four groups: sham group, limb ischemia group, cerebral ischemia group and LIP group. LIP was performedby occluding the bilateral femoral arteries for 10 min 3 times in an interval of 10 min. Global cerebral ischemia was underwent by occluding thebilateral common carotid arteries for 8 min immediately after LIP.Assays for apoptosis of the hippocampal neurons were biologically andmorphologically performed using gel electrophoresis. TUNEL and AO/EB staining. Characteristic DNA ladder was cleary visualized with gelelectrophoresis in the hippocampus in cerebral ischemia group, but not in LIP group. The number of TUNEL-positive cells in the CA1hippocampus was significantly reduced by LIP from 69.8±12 (cerebral ischemia group) to 17.8±5.8 (P<0.01). AO/EB staining also showeda reduction of apoptosis in LIP group compared with cerebral ischemia group. These results suggest that LIP can inhibit hippocampal neuronalapoptosis induced by cerebral ischemia-reperfusion, which contributes to the protection against the delayed neuronal death induced bycerebral ischemic insult.更多还原