L-精氨酸对大鼠蛛网膜下腔出血脑组织血供的改善作用

目的　探讨L 精氨酸 (L Arg)对蛛网膜下腔出血(SAH)后继发性脑缺血的影响。方法　用血管内脑底动脉环穿刺法建立大鼠SAH模型 ,将动物分为假手术 (SO)组、SAH组和SAH +L Arg组。L Arg于术前 3 0min按 50 0mg·kg- 1ip ,每 6h追加 1次。动态检测 2 4h内大脑顶叶皮层局部脑血流量 (rCBF) ,测定不同时间点血清一氧化氮 (NO ,NO-2 /NO-3 )水平 ,同时监测血压和血气。结果　假手术对rCBF和血清NO含量无显著影响。SAH组术后rCBF迅速降低并持续 2 4h ;SAH组血清NO水平于术后 1h开始下降 ,持续 2 4h ;与SAH组比较 ,SAH +L Arg组rCBF下降的速度减慢且程度减轻 ;血清NO水平下降的程度减轻。结论　L Arg可部分补偿SAH后血清NO不足 ,从而缓解继发性脑缺血程度

Improvement of cerebral blood perfusion by L-arginine following subarachnoid hemorrhage in rats

AIM To determine the effect of L-arginin e on cerebral blood perfusion following subarachnoid hemorrhage(SAH) in rats. METHODS Endovascular perforating SAH models were replicated in Wista r rats, and animals were divided into sham-operated group, SAH group and SAH+ L-arginine group. Dynamic changes of regional cerebral blood flow (rCBF) with in 24 hours were measured and serum nitric oxide(NO, NO - 2/NO - 3)levels at different time points within 24 hours were detected. Mean arterial blood pre ssure and blood gas were monitored during the experiment. RESULTS No obvious change in physiological parameters in the three groups was observed . rCBF and serum nitric oxide level at every time point after operation in SAH g roup were lower than those in sham-operated group. Pathological alterations abo ve in SAH+L-arginine group were less obvious than those in SAH group. CONCLUSION L-arginine, by antagonizing the decrease of nitric oxi de, exerts protective effect on secondary cerebral ischemia following SAH.