急性脑缺血模型大鼠胃肠黏膜血流变化及组织形态学的改变

The dynamic changes of gastrointestinal blood flow and the histolosical changes of gastrointestinal mucosa in rats with cerebral ischemia

目的探讨急性脑缺血模型大鼠早期胃肠黏膜血流变化及组织形态学的改变。方法雄性Wistar大鼠64只,随机分为两组:脑缺血模型组(32只)和假手术对照组(32只),两组大鼠分别按术后6、12、24、48 h时相点分为4个亚组(每组均为8只)。测定胃肠黏膜血流量,光镜和透射电镜下观察肠黏膜组织形态学变化。结果脑缺血组各时相点的胃、肠黏膜血流量(mV)分别为术后6 h(148±13、34．5±3．2),12 h(102±11、22．7±1．9),24 h(125±10、26．2±4．3),48 h(137±15、30．5±4．1),均低于对照组同时相点的术后6 h(285±17、46．8±5．4),12 h(301±21、50．1±3．6),24 h (294±24、45．4±4．1),48 h(318±11、48．7±7．3),两组比较,差异有统计学意义(P<O．05)。光镜下可见脑缺血组肠黏膜上皮细胞受损,电镜下可见肠黏膜细胞间紧密连接较对照组增宽。结论急性脑缺血后早期大鼠胃、肠黏膜血流量下降,这是导致大鼠胃、肠黏膜受损病理生理变化的重要因素之一。

Objective To investigate the changes of the gastrointestinal blood flow and the damage of gastrointestinal mucosa in cerebral ischemia rats. Methods Sixty and four healthy male Wistar rats were divided into two groups randomly： cerebral ischemla model group （n=32） who suffered from cerebral ischemia by Yuji＇s method, and control group （n=32） who suffered from sham operation. Each group was divided into four subgroups that were studied in 6 h,12 h,24 h,and 48 h after operation （n=8, for each subgroup）. The gastrointestinal blood flow was detected by Laser Doppler Flowmetry, the damage of the intestinal mucosa was observed under microscope and electronmicroscope. Results The gastrointestinal blood flow in cerebral ischemia group [（mV） post-operation 6 h （14.8±13;34. 5±3. 2） ;12 h（102±11;22.7±1.9） ;24 h（125±10;26.2±4.3） ;48 h（137±15;30.5±4. 1）] were significantly lower than that in control group （6 h （285±17; 46. 8±5.4） ;12 h（301±21,50.1±3.6）;24 h（294±24;45.4±4.1）;48 h（318±11;48. 7±7.3）;（P〈O. 05）, the intestinal mucosa was damaged and the intercellular space of intestinal mucosa was increased in cerebral ischemia group, when compared with the control group. Conclusions The decrease of gastrointestinal blood flow plays an important role in the stress ralated damage of gastrointestinal mucosa in cerebral ischemia rats in early stage.