同型半胱氨酸对大鼠血管平滑肌细胞增殖的作用

血中同型半胱氨酸（ｈｏｍｏｃｙｓｔｅｉｎｅ，ＨＣＹ）浓度的升高已成为动脉粥样硬化发生的一个独立危险因子．为进一步阐明ＨＣＹ促进血管平滑肌细胞（ｖａｓｃｕｌａｒｓｍｏｏｔｈｍｕｓｃｌｅｃｅｌｓ，ＶＳＭＣｓ）增殖，从而引起动脉粥样硬化发生的机理．本实验采用细胞计数、３Ｈ－ＴｄＲ参入、细胞周期分析、Ｎｏｒｔｈｅｒｎ杂交方法证明，一定剂量的ＨＣＹ可促进离体培养的ＷＫＹ大鼠血管平滑肌细胞增殖，使其ＤＮＡ合成增加，细胞周期中Ｓ期细胞所占比例增加４３％，并促进ｃ－ｍｙｃ与ｃ－ｆｏｓ原癌基因ｍＲＮＡ表达增加．提示ＨＣＹ可能通过促进ＶＳＭＣｓ增殖而诱发动脉粥样硬化

Effect of Homocysteine on Proliferation of Vascular Smooth Muscle Cells

There is increasing evidence that a raised blood levels of homocysteine(HCY) is recognized as an independent risk factor for atherosclerotic disease.But the mechanism by which these elevated levels cause atherosclerosis is unknown.To understand the role of HCY in the pathogenesis of atherosclerosis,the effect of HCY on proliferation of the cultured vascular smooth muscle cells (VSMCs) were studied by means of cell counts, 3 H thymidine( 3 H TdR) incorporation,cell cycle analysis,as well as the expression of mRNA of c myc and c fos oncogene by Northern blot,The result showed that HCY added into the culture at different concentrations and different time could cause a dose dependent increase in cell number,DNA synthesis;the number of S phase cells in cell cycle was increase by 43% at 0 5 mmol/L HCY as compared with the control.The mRNA levels of c myc and c fos at different concentrations were also increased.The growth promoting effect of HCY on VSMCs shows an important mechanism to explain homocysteine induced atherosclerosis.