大鼠局灶性脑缺血再灌注后皮质神经元微血管构筑和血脑屏障的变化及丁苯酞的保护作用❋

摘要

目的：：观察大鼠脑缺血再灌注损伤后皮质微血管的变化,探讨丁苯酞对其作用。方法：线栓法制备大鼠脑缺血再灌注模型；单宁酸氯化铁媒染法显示大脑皮质微血管,Mivnt 图像分析系统定量分析微血管密度(MVD)和微血管面积密度(MVA)；干湿重法检测脑含水量,透射电镜观察血脑屏障超微结构。结果：与假手术组相比,缺血再灌注组大鼠皮质微血管绝大部分闭合或僵直,MVD 和 MVA 显著下降,脑含水量明显升高,电镜观察微血管腔狭窄,内皮细胞核固缩。丁苯酞组微血管形态好转,MVD 和 MVA 升高,脑水肿和血脑屏障损伤程度均减轻。结论：丁苯酞可改善大鼠脑皮质微血管形态,减轻脑水肿和血脑屏障损伤,对脑缺血再灌注损伤有一定的预防性保护作用。%Obj ective :To investigate the protection effect of 3-n-butylphthalide (NBP)on the microvascular architecture,brain water content and blood-brain barrier (BBB)in rats with focal cerebral ischemia/reperfusion.Methods :The method of middle cerebral artery occlusion (MCAO ) through thread approach was used to establish the model of focal brain ischemia/reperfusion (I/R).TA-Fe method was applied to observe the microvascular architecture of the cerebral cortex.Mivnt image analysis system was used to analyze the microvessel density (MVD)and the microvessel area density (MVA)of the cerebral cortex quantitatively;The degree of brain edema was analyzed through dry/wet weight measurement,and the ultrastructure changes of BBB were observed by transmission electron microscopy.Results :Compared to the sham group,most of the microvasculars were closed or stiff,MVD and MVA were decreased sharply,brain water content was increased obviously,the microvascular vessels became narrow or occlusive,the nucleus of endothelial cell shrinked in microvessels,and the connected space of endothelial cells increased in the I/R group.Compared with the I/R group,the count of closed microvessels decreased,MVD and MVA increased,and the degree of brain edema and injury of BBB were reduced in the NBP group. Conclusion :NBP can improve microvascular architecture,and reduce the degree of brain edema and injury of BBB.There is a protective effect of NBP on the cerebral cortex with focal cerebral ischemia/reperfusion in rats.