大鼠蛛网膜下腔出血后兴奋性氨基酸对脑微循环的影响

Study of excitatory amino acid of cerebral microcirculation after SAH

目的探讨蛛网膜下腔出血后氧化应激链中兴奋性氨基酸对脑微循环的影响。方法颈内血管穿刺法制作大鼠蛛网膜下腔出血模型。实验共分3组,出血模型3天组与急性期组(对照)。其中,出血后3天组又分2组,一组大鼠确定海马CA3区,另一组确定侧脑室区,分别采用微量进样器直接注射兴奋性氨基酸类似物海人酸(KA)与肾上腺髓质素(ADM),激光多普勒监测,观察并对比三者脑表面局部血流灌注量的变化趋势。结果ADM能提高SAH后脑表面局部微循环血流灌注量,KA能、降低其脑表面局部微循环血流灌注量。结论SAH后产生的氧化应激链中兴奋性氨基酸能够显著降低脑表面局部微循环血流灌注量。

Objective To explore the effect of excitatory amino acids on cerebral microcirculation in the chain of oxidative stress after subarachnoid hemorrhage. Methods Subarachnoid hemorrhage model was es-tablished by internal carotid vascular puncture and then divided into 3-day group and acute phase group （sham）. The rats were divided into three groups. In the hemorrhage group, rats were divided into 2 groups after 3 days. The rat heads were fastened by brain stereotactic apparatus, and removed skull to open a win-dow for the dura mater friction. Which is the bleeding 3-day group. Respectively positioning chimney bregma and posterior fontanelle lambda points, with the former chimney bregma point of medial lateral （ML） in the middle of the horizontal distance, and dorsal ventral （DV） back abdomen distance and Anterior posterior （AP） before and after the distance measurement, a set of rat hippocampal CA3 area was determined, and another group of lateral ventricle region was determined. Trace samplers were used respectively to directly inject excitatory amino acid analogues kainic acid （KA） and adrenal medullary quality （ADM）, with a laser doppler monitoring. The trends of brain surface local blood flow perfusion were observed and compared. Results ADM significantly increased the local microcirculation perfusion of SAH back surface, KA significantly reduced the brain surface local microcirculation perfusion. Conclusions The excitatory amino acids can significantly reduce brain surface local microcirculation perfusion in the chain of oxidatie stress after SAH.