大鼠蛛网膜下腔出血后早期海马MMP.doc

蛛网膜下腔出血后早期海马MMP-9的表达与海马神经元凋亡的相关性研究 郭宗铎，孙晓川，何朝晖，蒋 理，林 斌（重庆医科大学附属第一医院神经外科，重庆 400016） 摘要：目的 观察大鼠蛛网膜下腔出血后早期海马基质金属蛋白酶9的表达和海马神经细胞凋亡，及两者之间的关系，探讨基质金属蛋白酶9参与早期脑损伤的机制。方法 成年雄性SD大鼠108只，分为假手术组和蛛血组。采用经额蛛网膜下腔插管至Willis环方法建立蛛血模型，在蛛血后6、12、24、48、72 h，应用明胶酶谱法方法检测大鼠海马基质金属蛋白酶9的活性；免疫组化方法检测细胞外基质层粘连蛋白的表达；同时应用原位末端标记法检测海马神经元凋亡。结果 明胶酶谱法方法显示：大鼠蛛血后12h海马基质金属蛋白酶9活性明显升高，24h达到高峰，并于48h开始下降，72h时仍高于假手术组水平（P﹤0.01）；免疫组化方法显示：大鼠蛛血后12h海马层粘连蛋白表达开始下降，24h降至最低，并于48h表达开始升高，蛛血后72h海马层粘连蛋白表达仍低于假手术组水平（P﹤0.01）；原位末端标记法检测发现大鼠蛛血后12h海马凋亡阳性细胞数开始增加，24h达到高峰，并于48h表达开始下降，蛛血后72h海马凋亡阳性细胞数仍较高（P﹤0.01）。结论 大鼠蛛血后基质金属蛋白酶9可能通过降解其底物层粘连蛋白，导致海马神经细胞发生失巢凋亡，参与EBI的病理过程。 关键词：基质金属蛋白酶 9； 蛛网膜下腔出血；层粘连蛋白；早期脑损伤；失巢凋亡 中图分类号：R743.35 文献标识码：A Study on the association between the expression of MMP-9 and neuronal apoptosis of hippocampus in early brain injury after subarachnoid hemorrhage of rats GUO Zong-duo, SUN Xiao-chuan, HE Zhao-hui, JIANG Li, LIN Bin (Department of Neurosurgery, First Hospital of Chongqing Medical University, Chongqing 400016, China) Abstract: Objective To observe the relation between the activity of MMP-9 and neuronal apoptosis of hippocampus and investigate the mechanism of MMP-9 involved in early brain injury after SAH. Methods 108 adult male SD rats were randomly divided into two groups: the sham-operated group and SAH group. The SAH model was induced by injecting 300μl of autologous arterial blood into the subarachnoid space near the circle of Willis via a cannula in an artificial hole between the olfactory bulb and frontal lobe. Expressions of the protein activity of MMP-9 in hippocampus were examined at 6, 12, 24, 48, 72h by gelatin-containing SDSzymography. The changes of laminin, the component of extracellular matrix, was examined by immunohistochemistry. Meanwhile, the neuronal apoptosis of hippocampus were measured by TUNEL. Results (1)The zymography showed: the expression of the protein activity of MMP-9 increased dramatically at 12h and reached the peak at 24h, then decreased gradually and to the lowest level at