实验性高胆固醇血症家兔血液流变特性的改变与AS形成关系的研究

STUDY ON THE RELATIONS BETWEEN HEMORHEOLOGICAL CHANGES AND FORMATION OF ATHEROSCLEROSIS IN EXPERIMENTAL HYPERCHOLESTEROLEMIC RABBITS

目的 :了解实验性高胆固醇血症家兔血液流变特性的改变与动脉粥样硬化形成的关系。方法 :健康家兔 80只 ,随机分为实验组 (AG) 6 0只和对照组 (CG) 2 0只。各组又均分为 4个亚组 ,即AG1～AG4和CGl～CG4。AG组每只给予胆固醇粉 1g/d ,在喂养的第 2、4、8和 12周分别观察AGl～CGl、AG2～CG2、AG3～CG3和AG4～CG4的主动脉粥样硬化 (AS)病变及相应血液流变特性的变化。结果 :在兔AS阶段性进程中血清总胆固醇浓度、全血粘度、血浆粘度、红细胞硬度指数、红细胞聚集指数及全血粘弹性呈升高趋势 ,而红细胞变形参数呈下降趋势。低切全血粘度与红细胞聚集指数间 (r =0 .6 2 8,0 .6 84,0 .881,P <0 .0 1)、弹性模量与红细胞硬度指数 (r =0 .5 78～0 .842 ,P <0 .0 5～ 0 .0 0 1)和动粘度 (r=0 .5 13～ 0 .848,P <0 .0 5～ 0 .0 0 1)间均存在正相关关系 ,而红细胞变形参数与高切全血粘度 (r=- 0 .5 91～ - 0 .813 ,P <0 .0 5～ 0 .0 0 1)和弹性模量 (r=- 0 .5 6 9～ - 0 .784,P <0 .0 5～ 0 .0 0 1)间有负相关关系。结论 :除高胆固醇血症外 ,血流变特性特别是红细胞变形能力降低和全血粘弹性的改变亦是AS的重要成因。

Aim:To investigate the relations between hemorheological changes and formation of atherosclerosis(AS) in experimental hypercholesterolemic rabbits.Methods:80 rabbits were randomly divided into experimental group( n =60) and control group( n =20).Each of the two groups was also equally divided into four experimental subgroups and four control ones. Each rabbit of the experimental group was fed with cholesterol powder (1 g/d). At the 2 nd,4 th ,8 th and 12 th week, the hemorheological parameters were tested and the pathologic alteration of atherosclerosis(AS) in the aorta was also observed.Results:Total cholesterol concentration in serum,high or low share rate blood viscosity (η bh or η bl ),plasma viscosity, erythrocyte rigidity index(TK value),erythrocyte aggregation index (EAI) and viscoelastic properties of whole blood were significantly increased ( P <0.05～0.01) and erythrocyte deformability parameters(α) were significantly decreased ( P <0.05～0.001) in the course of AS. η b1 positively correlated with EAI ( r =0.628, 0.648 ,0.881, P <0.01), and whole blood dynamic modulus(G') positively correlated with TK value ( r =0.578～0.842, P <0.05～0.001) and whole blood dynamic viscosity ( r =-0.513～-0.848, P <0.05～0.001).α negatively correlated with η bh ( r = -0.591 ～-0.813, P <0.05～0.001) and G'( r =-0.569～-0.784, P <0.05～0.001).Conclusion:Both hypercholesterolemia and decreased erythrocyte deformability and changes of hemorheological characters play an important role in the pathogenesis of AS in cholesterol-fed rabbits.