大鼠局灶性脑缺血后受累动脉调节功能受损  

Impaired vasoactive function of affected artery after focal cerebral ischemia in rat

作　　者：张合亮[1] 马廉亭[1] 刘美利[2] 姚国杰[2] 徐军[2] 邵伟[2] 杜洪鹏[2] 席永强 廖旭兴[1] 

机构地区：[1]广州军区武汉总医院神经外科,武汉430070 [2]滨州医学院附属医院神经外科 [3]山西垣曲县人民医院神经外科

出　　处：《中华神经科杂志》2010年第6期440-443,共4页Chinese Journal of Neurology

摘　　要：目的研究脑缺血对受累动脉调节功能的影响，探讨缺血再灌注损伤发生的可能机制。方法线栓法制作大鼠大脑中动脉梗死模型，2h后取受累侧大脑中动脉游离血管段，测量压力和血管活性物质诱发的动脉直径变化，据此计算出膨胀性、肌源性张力及对5-羟色胺和乙酰胆碱的反应性，与对照组对比。结果低压区，缺血动脉肌源性张力增加[40mmHg（1mmHg=0．133kPa）时，19．3％±0．4％与10．0％±0．2％，t=20．568，P=0．000]，直径缩小（F=9．572，P=0．009）；高压区肌源性张力下降（120mmHg时，12．0％±0．2％与21．8％±0．4％，t=-23．575，P=0．000），动脉易膨胀，直径增大；生理压力区，肌源性反应变化不明显（80mmHg时，18．7％±0．4％与18．3％±0．3％，t=0．635，P=0．537）。缺血后动脉对5-羟色胺和乙酰胆碱反应性下降。结论脑缺血可引起受累动脉调节功能下降，动脉再通后易出现缺血区的过度灌注，造成缺血再灌注损伤。Objective To investigate the effect of cerebral ischemia on functional parameters of affected arteries and probe into the possible pathogenesis of ischemia-reperfusion injury. Methods Intraluminal suture ischemie model was used by occlusion of left middle cerebral artery in rats. Two hours later, the middle cerebral artery segments were isolated from both isebemia and control groups for measurement of changes in vessel diameter induced by increasing pressure and vasoactive compounds. And then, distensibility, myogenic tone, reactivity to 5-HT and ACh were calculated and compared between groups. Results In lower pressure range, ischemic vessels showed an increased myogenic tone （at 40 mm Hg, 1 mm Hg = 0. 133 kPa, 19. 3%± 0. 4% vs 10. 0%± 0. 2% , t = 20. 568, P = 0. 000） and decreased diameter. In higher pressure range, ischemic vessels showed an increased diameter, distensibility and decreased myogenic tone （at 120 mm Hg, 12. 0%±0.2% vs 21.8% ±0.4%, t = -23.575, P= 0. 000 ）. In normal pressure range, myogenic tone was not altered after ischemia. Both groups constricted to 5-HT and dilated to ACh, however, the response was significantly diminished after ischemia. Conclusion These findings demonstrate that contractile and diastolic function of affected artery was impaired after isehemia, a result that may contribute to isehemia-reperfusion injury by losing upstream cerebrovaseular resistance and increasing perfusion on the microcirculation.

关 键 词：脑缺血 大脑中动脉 再灌注损伤 血清素 乙酰胆碱 

分 类 号：R743.3[医药卫生—神经病学与精神病学]