大鼠急性局灶性脑缺血再灌注损伤血浆一氧化氮含量的动态变化

The changes of nitric oxide concentration in plasma during acute focal cerebral ischemia and reperfusion in rats

为探讨一氧化氮和神经元性一氧化氮是否参与急性局灶性脑缺血再灌注的发病机理，用栓线法建立大脑中动脉阻塞模型大鼠，观察急性局灶性脑缺血再灌注损伤血浆一氧化氮含量的动态变化和神经元型一氧化氮合酶抑制剂———７硝基吲唑对再灌注期一氧化氮含量的影响．结果，脑缺血３０ｍｉｎ血浆一氧化氮含量明显升高，缺血３ｈ组一氧化氮含量下降，接近对照组；缺血３ｈ、再灌注３０ｍｉｎ组血浆一氧化氮含量再次升高，再灌注３ｈ组一氧化氮含量又下降，但仍高于对照组．７硝基吲唑（２５ｍｇ／ｋｇ）能显著抑制缺血３ｈ、再灌注３０ｍｉｎ升高的血浆一氧化氮水平．７硝基吲唑的作用可被Ｌ精氨酸（３００ｍｇ／ｋｇ）逆转，而Ｄ精氨酸（３００ｍｇ／ｋｇ）无效．

The aim of the study was to preliminarily probe whether nitric oxide(NO) and neuronal NO was involved in the pathophysiology of acute focal cerebral ischemia and reperfusion. On the basis of the rat model of a middle cerebral artery occlusion(MCAO) by an intraluminal filament, it is investigated the alterations of NO concentration in plasma during and after focal cerebral ischemia and the effect of neuronal NO synthase inhibitor 7 nitroindazole (7 NI) on NO concentration in 30min reperfusion after 3h MCAO. The results showed that NO content in plasma significantly increased in 30min cerebral ischemia and then decreased in 3h ischemia;NO content reincreased in 30min reperfusion after 3h MCAO, but in 3h reperfusion after 3h MCAO redecreased. 7 NI (25mg/kg) significantly inhibited NO content in plasma in 30min reperfusion after 3h MCAO. The effect of 7 NI on NO content was reversed by L arginine (300mg/kg) , but not by D arginine (300mg/kg) .