Cystatin C对SAH后早期脑血管痉挛防治及与自噬相关性的实验研究

目的观察sD大鼠蛛网膜下腔出血（subarachnoidhemorrhage，SAH）后白噬在基底动脉壁的表达，探讨半胱氨酸蛋白酶抑制NC（CystatinC）对SD大鼠SAH后早期脑血管痉挛（cerebralvasospasm，CVS）的干预作用，并分析其与自噬（autophagy）的相关性。方法40只SD大鼠随机分为对照组（A组）、蛛网膜下腔出血组（B组）、安慰剂组（C组）、CystatinC治疗组（D组），每组10只。对照组大鼠在枕大池单纯注入生理盐水，其余三组大鼠在枕大池一次性注血制作SAH模型，治疗组在注血前30min~_枕大池注／kCystatinC水溶剂0．1ml（10μg／O．1m1），安慰剂组在注血前30min经枕大池注入等量生理盐水。均于术后48h处死大鼠，取脑基底动脉部位标本作病理检查，测定基底动脉内径周长和血管壁厚度，以此评价有无脑血管痉挛及程度；应用自噬标记抗体LC3和Beclin-1对各组大鼠基底动脉行Westernblot分析。结果SAH组和安慰剂组大鼠基底动脉内径周长较对照组明显缩短（P〈O．01），血管壁厚度明显增加（P〈O．01）。CystatinC治疗组基底动脉内径周长增大，管壁增厚程度减轻以及CVS值下降，与SAIl组及安慰剂组比较差异有统计学意义（P〈O．01）。Westemblot分析显示自噬相关指标LC3和Beclin-1在对照组呈低表达，在SAH组及安慰剂组表达明显增高，与对照组比较差异有统计学意义（p〈0．05）。在Cystatinc治疗组，LC3和Beclin．1的表达进一步增高，与SAHN及安慰剂组比较差异有统计学意义（P〈O．01）。结论SAH后自噬在基底动脉壁被激活，提示自噬可能作为一种保护机制参与了CVS的病理及生理过程，经枕大池注入cys诅tinC能诱导白噬在基底动脉壁的高表达，对CVS有一定的防治作用。

Objective To investigate the expressions ofautophagy in BA （ basilar artery ） walls following subarachnoid hemonimge （ SAH ） in rats, and to study the effect of cystatin C in the prevention of cerebral vasospasm （ CVS ） and its relationships to autophagy. Methods 40 health male Sprague-Dawley （ SD ） rats were assigned randomly into following groups：Control group （ injected normal sodium into cistema magna only ） , SAH group, Vehicle group, Cystatin C therapy group （ n=10, respectively ） .All SAIl animals were subjected to in jection of 0.3 ml flesh arterial, non-heparinized blood into Cistema magna to establish SAH model. 30 minutes before the blood injection, an amount of 0. l rrd of the Cystatin C （ 10 μg/0.1ml ） was administered directly into the cistema magna in the Cystatin C therapy groups, while Vehicle animals received an equal volume of NS. 48 hours later, we observed morphological changes and the expression of autophagy in BA walls by pathological section and West em Not analysis. Results The inner perimeter of basal arteries （ BA ） in SAH group and vehicle group got smaller, and the wall thickness of basal arteries bec^ne thicker than control group （ P〈0.01 ） . Compared with SAH and Vehicle groups,the inner perimeter of BA in treatment group was expanded and thickness of BA walls were decreased with a statistical difference （ P〈O.O1 ） . Western blot showed： the expression of autophagy in BAwalls was low in con-lrol group, the activity of autophagy was significantly increased in the rats of SAH and vehicle groups （ -P〈0.05 ） , the increased activity of autophagy was further markedly upregulated by CysC treatment （ P〈0.01 ） . Conelusiolx~ The increased expression of autophagy in the BA walls following SAIl suggests that autophagy may participate in the pathological course of CVS. Activation of autophagy induced by Cys C results in attenuation of CVS in SAH models.