急性颅脑损伤脑微血管形态学改变的实验研究

目的：探讨急性颅脑损伤脑微血管形态学改变。方法：制作大鼠液压冲击脑损伤模型,脑微血管墨汁灌注,制作切透明标本,利用Mins-2000图像分析系统测定微血管直径和面积密度,制备扫描电镜脑组织标本,观察微血管形态学的改变。结果：扫描电镜观察有小血管破裂红细胞漏出,部分血管扭血,有些区域出现无血管区。受伤48h和72h,微血管内 有微形成,周围组织间隙增宽。部分血管分析示脑外伤3h微血管的直径和血管面积密度均较对照组降低（P＜0．01）,受伤12h后,微血管直径均较对照组增加（P＜0．01）,胆血管面积仍较正常低（P＜0．05）。结论：脑微循环功能失调可能是导致脑外伤后继发性脑血缺氧的重要原因。

An Experimental Study on Changes of Microvasculature After Acute Brain Injury in Rats

Objectve To study the changes of the cerebral microvasclature after acute brain injury. Methods Using experimental traumatic brain injury in rats,the morphologic changes of the cerebral microvasculature were inspected by scanning electron microscopy; the shape of cerebral vessels was observed by the prepared Chinese ink irrigation, the width and volume fraction of the cerebral microvasculature were tested and analyzed by stereographic method respectively. Results At 3 hr, the changes of cerebral microvasculature including: the width of lumen of microvasculature was narrowed (P<0.01); diseruption of the vessels and no vessel area presented in some areas. at 48hr and 72 hr after traumatic brain,the width of capillaries and small veins was widened(P<0.01),but the percentage of microvasculature volume fraction was smaller(P<0.05),the permeability of microvasculature was increased, and the thrombus was found in microvasculature. Conclusion Disorder of brain microcirculation results in secondary brain ischemia after cerebral microvasculature injuries.