一氧化氮在大鼠创伤局部微循环灌流减少中的作用

Role of nitric oxide in the decrease of local microcircular perfusion in amputated rats

目的和方法：用激光多普勒微循环血流仪测定大鼠断肢局部微循环血液灌流量，用比色法测定血浆亚硝酸盐（ＮＯ２－）水平间接反映血浆一氧化氮（ＮＯ）含量。结果：（１）断肢局部微循环血液灌流量在断肢Ｏ、１、２和３ｈ均明显下降，局部股静脉血浆ＮＯ２－含量在断肢２、３ｈ显著降低，断肢２、３ｈ局部股静脉血浆ＮＯ２－水平与局部微循环血液灌流量呈显著正相关。（２）ＮＯ合成底物左旋精氨酸（Ｌ－Ａｒｇ）能改善断肢２、３ｈ的局部微循环血液灌流量，一氧化氮合成抑制剂左旋单甲基精氨酸（Ｌ－ＮＭＡ），可抑制此作用。（３）断肢３ｈ局部股静脉血浆ＮＯ２－水平Ｌ－Ａｒｇ组明显高于生理盐水（ＮＳ）组（Ｐ＜００５），Ｌ－Ａｒｇ合用Ｌ－ＮＭＡ组则明显低于ＮＳ组（Ｐ＜００５）。结论：断肢创伤通过内源性Ｌ－Ａｒｇ－ＮＯ通路而降低ＮＯ生成，参与断肢局部２。

AIM and METHOD: The microciculatory perfusion was measured with Laser Doppler Flowmeter and the plasma NO (nitric oride) level was detectred by measuring the content of plasma nitrite with colorimetric method. RESULTS: 1. The local microciculatory perfusion of amputated rats decreased significantly at Oh, 1, 2, and 3h after amputation. The concentration of loal femoral artery plasma NO - 2 went down at 2 and 3h after amputation. There was a positive correlation between the local femoral plasma NO levels at 2, 3h of amputation and the microciculatory perfusion. 2. Administrated NO synthesis substrate L-arginine(L-Arg), the blood microciculatory perfusion increased significantly at 3 and 3h after amputation. Given NO synthesis inhibitor L-N G-monomethyl arginine(L-NMA), the local microciculatory perfusion was reduced significantly at 1, 2, and 3h after amputation. 3. The local femoral vein plasma NO - 2 contents were higher in L-Arg group than that in NS group, In L-Arg+L-NMA group, NO - 2 contents was lower than that in NS group. CONCLUSIOW: This traumatic stimulation may reduce the local NO level through endogenous L-Arg-NO pathway and takes part in the pathogenesis of local vasospasm in amputated rats at 2 and 3h.