大鼠脑出血后细胞色素c表达和神经细胞凋亡的关系及牛磺酸熊去氧胆酸的干预作用

Study on the relationship of cytochrome C expression and apoptosis of neuron in rats following intracerebral hemorrhage and effect of Tauroursodeoxycholic acid on it

目的 研究大鼠脑出血（ICH）后细胞色素c（cytc）表达和神经细胞凋亡的关系，探讨牛磺酸熊去氧胆酸（Tudca）的干预作用及其机制。方法 用VII型胶原酶注入到大鼠右侧苍白球诱导ICH模型。用凋亡原位末端标记技术（TUNEL）和免疫组化方法检测血肿周围神经细胞凋亡和cytc表达的动态变化。透射电镜观察术后3d血肿周围神经元超微结构的变化。结果：ICH后6hcytc表达开始增加，1d达高峰．此后逐渐减少，7d时回落至假手术组水平。ICH后6h血肿周边组织可见TUNEL阳性细胞．3d达高峰。然后逐渐减少，7d、10d时仍见较多凋亡细胞。ICH后7d内cytc表达和神经细胞凋亡呈正相关（r=0．6357，P〈0．01）。Tudca治疗组cytc和TUNEL阳性细胞数较模型组明显减少（P〈0．05～0．01），神经元超微结构改变亦比模型组减轻。结论 ICH后血肿周围神经细胞损伤有凋亡机制参与，cytc释放是神经细胞凋亡的一个关键事件，Tudca可以有效减轻脑出血后的细胞凋亡，其机制之一是抑制凋亡通路cytc的释放。

Objective To observe the relationship of cytochrome C expression and apoptosis of neuron,and investigate the effect of Tauroursodeoxycholic acid（Tudca） on it. Methods ICH models was induced in rats by injection of type Ⅶ collagenase into the the right globas pallidus. By the methods of TUNEL and immunohistochemistry,We investigated the dynamic changes of apoptosis and the expression of cytochrome C in the tissue surrounding hematoma in ICH rats. Results Cytc expression was increased at 6h,peaked at ld and then declined, and then returned to the level of pseudo-operation group on 7d postoperative. TUNEL-positive cells appeared in the model group 6h after collagenase injection,peaked at 3d and then declined,but after 7d there were still many apoptotic cells. There was a positive correlation between cytc expression and cell apoptosis in 7d after ICH （r= 0. 6357,P〈0. 01 ）. cytc-positive neurons and the apoptotic cells of Tudca group greatly decreased than those of model group （P〈0.05～0. 01）. The pathological changes of the treated group were milder than the model group on 3d postoperative. Conclusion Apotosis is a pattern of death after intracerebral hemorrhage,and the release of cytc from mitochondria to cytosol is a critical step in apoptotic cell death after ICH. Tudca can effectively alleviate apoptosis after ICH by preventing cytc release.