一氧化氮、一氧化氮合成酶在免疫性血管炎致动脉粥样硬化中的作用

目的探讨一氧化氮(NO)、一氧化氮合成酶(NOS)在免疫性血管炎致动脉粥样硬化(AS)中的作用。方法4周龄雄性大耳兔24只分为3组。A组:基础饲料喂养对照组8只;B组:胆固醇喂饲组8只;C组:10%牛血清清蛋白注射并喂饲胆固醇饲料8只。实验满4周,A、B、C3组分别取心脏做主动脉组织病理学检查,主动脉血管弹力纤维染色及NOS组织化学染色,测血清NO和血浆血管内皮素(ET)含量。结果B组出现轻度AS,内弹力膜不完整;C组出现严重AS,内弹力膜断裂。3组NOS均呈阳性着色反应,C组阳性着色区域较A、B组明显扩大。C组与B组比较,其脂质斑块面积(PA)增大、小动脉粥样硬化发生率(IA)增高、NOS平均光密度(A)增高,血浆ET含量升高,血清NO含量降低,均有显著差异(P<0.01)。结论免疫性血管炎为AS发病的危险因素,NO/ET平衡失调,NOS活性异常可能参与免疫性血管炎致AS形成的病理过程。

Effect of Nitric Oxide, Nitric Oxide Synthetase on Arteriosclerosis Caused by Immune Vasculitis

Objective To study the effect of nitric oxide (NO), nitric oxide synthetase(NOS) in the arteriosclerosis(AS) caused by immune vasculitis. Methods There were 24 mature male rabbits, which were divided into three groups: 8 normal rabbits with formal feeding as eontrols(group A) ; 8 rabbits with cholesterol feeding (group B); 8 rabbits with cholesterol feeding and bovine serum albumin injection (group C) The rabbits of A, B , and C were sacrificed for the examination of aortic histopathology and aortic vascular elastic fiber staining and NOS histochemistry staining after 4 weeks, and the content of serum NO and plasma vascular endothelin was measured. Results The rabbits in group B had low-grade AS with incomplete mtraelastic membrane; group C had severe AS with breaking mtraelastic membrane . The positive staining inteasity in group C markedly increased and the scope of positive staining was extensive compared with group A and B. There were obvious differences in lipid plaque, average optical density of NOS and the bleeding levels of ET and NO(P<0.01). Conclusions The immune vasculitis is a new risky factor for AS. The imbalance of NO/ET and the unconventionally of the activity of NOS may result in the AS caused by immune vasculitis.