脑出血后继发血管源性脑水肿的机制研究

Studies on secondary vasogenic brain edema following intracerebral hemorrhage

目的 研究自发性脑出血 (Intracerebralhemorrhage,ICH)后血管源性脑水肿 (vasogenicbrainedema ,VBE)的发生机制。方法 采用立体定向技术制作实验性ICH模型 ,免疫组化、组化染色和HE染色分别观察血肿周围脑组织的内皮细胞粘附因子 (CD3 4 )、小胶质细胞、白细胞的动态变化。结果 ①假手术组大鼠脑组织未见白细胞浸润及小胶质细胞染色 ,而CD3 4 阳性微血管数最多 ;ICH 12h见血肿周围CD3 4 有所下降 ,72h达最低 ,7天后缓慢恢复到假手术组水平 ;②于ICH 6h血肿周围开始表达小胶质细胞 ,至 4 8h达高峰 ,持续 2周仍可见其少量表达 ;③ICH 12h可见白细胞浸润 ,4 8h数量最多 ,以后逐渐减少 ,2周时基本消失。各组之间及各组与假手术组之间比较差异显著 (P <0 .0 1) ;④ICH后小胶质细胞和CD3 4 表达呈负相关关系 (r =- 0 .770 ,P <0 .0 5 )。结论 ICH后血肿周围的炎症细胞介导的炎症反应参与了继发性血管源性脑水肿的形成。

Objective\ To investigate the mechanisms of vasogenic brain edema following spontaneous ICH.Methods\ The experimental ICH model in adult rats was made by stereotactic injecting quantitative autologous blood into the left caudate nucleus.Time course of CD\-\{34\} ,neutrophils and microglia of perihematoma were immunohistochemically or histochemically detected.Results\ ①The CD\-\{34\} positive microvasculars were maximal but no neutrophils and microglia were found in sham operating groups and CD\-\{34\} declined at 12 h(P<0.01)after ICH,minimal at 72 h,and recovered after 1 week; ②Microglia were expressed as early as 6 h(P<0.01)after blood injection and were maximal at 48 h,and persisted until 2 weeks; ③ neutrophils became apparent surrounding hematoma at 12 h(P<0.01)and were more abundant at 48 h and then decreased gradually till disappearing after 2 weeks;④The expression of microglia was negatively correlated with the CD\-\{34\} positive microvasculars(r= -0.770, P<0.05). Conclusion\ Inflammatory response which was induced by inflammatory cells may be involved in secondary vasogenic brain edema surrounding hematoma following ICH.