Influences of simvastatin in different doses on vascular endothelial function in patients with coronary atherosclerosis

Objective To observe the influences of simvastatin in different doses on vascular endothelial function in patients with coronary atherosclerosis. Methods The patients(n=133) were divided,according to the level of low-density lipoprotein-cholesterol(LDL-C),into 4 groups:40 mg group(LDL-C≥4.16 mmol/L,n=30,treated with simvastatin,40 mg/d),20 mg group(3.64 mmol/L≤LDL-C4.16 mmol/L,n=35,treated with simvastatin,20 mg/d),10 mg group(2.6 mmol/L≤LDL-C3.64 mmol/L,n=37,treated with simvastatin,10 mg/ d) and control group(LDL-C2.6 mmol/L,n=31,not treated with simvastatin). The changes of flow-mediated dilatation(FMD) and nitroglycerin-mediated dilatation(NMD) were detected by using color Doppler ultrasonic diagnostic apparatus. The content of serum nitric oxide(NO) was detected by using nitrate reductase method,and the levels of serum total cholesterol(TC),triglyceride(TG),LDL-C and high-density lipoprotein-cholesterol(HDL-C) were detected conventionally. Results Before treatment,the level of serum NO had no statistical difference in all simvastatin groups compared with control group(P0.05). After treatment for 8 w,the level of serum NO increased significantly in all simvastatin groups(P0.05),and had statistical difference compared with control group(P0.05). The level of NO had no obvious changes in control group before and after treatment(P0.05). Before treatment,the basis value of brachia diameter,FMD and NMD had no statistical difference between all simvastatin groups and control group(P0.05). After treatment for 8 w,the basis value of brachia diameter and NMD had no statistical difference in all simvastatin groups(P0.05) and FMD increased significantly,and the difference was statistically significant compared with control group(P0.05). The difference in NMD had no statistically significance between all simvastatin groups and control group(P0.05). Conclusion Simvastatin can increase the level of serum NO,improve vascular endothelial function in patients with coronary atherosclerosis,and there is no dose-effect relationship in its mechanism of ameliorating level of blood fat.