尼莫地平对蛛网膜下腔出血大鼠脑功能的改善作用

目的探讨尼莫地平对SAH大鼠脑功能改善作用,并分析相关机制.方法采用枕大池二次注血法建立大鼠SAH模型,通过神经行为学评分,经颅多普勒超声检测基底动脉的平均血流速度,HE染色法观察脑形态学改变,脑含水量检测分析尼莫地平对SAH的治疗机制.结果与假手术组相比,SAH组大鼠出现明显的神经运动功能障碍体征,其神经行为学评分明显降低;与SAH组相比,尼莫地平组大鼠神经运动功能障碍体征明显减轻,神经行为评分明显高于SAH组.颅超声多普勒检测结果表明:SAH组大脑基底动脉血流速度明显加快,而经过尼莫地平治疗后,其血流速度明显降低;HE染色发现:SAH组大鼠脑中可见明显的出血灶,神经元数目减少,神经元及神经胶质出现肿胀,尼莫地平能够明显减轻SAH后的脑损伤;大鼠SAH时,脑水含量明显增加,尼莫地平既能减轻血管源性脑水肿症状,又减轻细胞毒性脑水肿症状.结论尼莫地平能改善神经运动功能障碍,其机制与降低基底动脉血流速度、减轻神经细胞、胶质细胞肿胀及减轻脑水肿有关.

Improvement Effect of Nimodipine on Brain Function in Rats with Subarachnoid Hemorrhage

Objective To explore the improvement effect of nimodipine on brain function in rats with spontaneous subarachnoid hemorrhage and analyze the related mechanism. Method A reliable model of subarachnoid hemorrhage( SAH) was established by double injections of blood into the cistern magna in Wistar rats. The neurological score was performed according to Loeffler respectively. The artery blood flow velocity was measured by transcranial doppler sonography ( TCD ) and the brain morphological change was measured by HE staining. The cerebral water content was measured by dry-wet weight method. Result Compared to the sham group,SAH group appeared obvious sign of motor dysfunction and lower neuroethological score;Compared with SAH group,the neuroethological score of nimodipine group increased obviously,suggesting that nimodipine can lessen nervous system dysfunction. The blood in basilar artery of SAH group flowed much faster than that of the sham group through TCD detection, while nimodipine could reduce its velocity. HE staining showed that the number of neuron decreased in SAH group,neuron and glia swell as well as bleeding lesions could also be seen in this group. On the contrary, the number of necrosis neuron in nimodipine group decreased, which implied that nimodipine had protective effect on brain damage induced by SAH. In the sham group, cerebral water content increased obviously,while nimodipine could lessen the brain edema both angiogenic and cytotoxic. Conclusion Nimodipine could improve the neuromotor dysfunction in rats with SAH. Its mechanism was related with reducing basilar artery blood flow velocity,relieving swelling of nerve and glial cells,and alleviating cerebral edema.