Abstract: Objective To investigate the effect and its mechanism of Guanxinning tablet on carotid atherosclerotic plaque in a rat model. Methods The rats were randomly divided into control group, model group (to construct carotid atherosclerosis plaque model), Guanxinning groups with low, medium and high dose of Guanxinning tablet (150,300 and 600 mg/kg), atorvastatin group (2 mg/kg), lithiumchloridemonohydrate(LiCl) (Wnt/β-catenin pathway activator) group (15 mg/kg), and Guanxinning plus LiCl group (600 mg/kg Guanxinning tablets+15 mg/kg LiCl), with 12 rats in each group. The intervention began at the third week and was administered once a day for 8 weeks. Olympus Au2700 automatic biochemical analyzer was used to detect the level of total cholesterol (TC), triglyceride (TG), low density lipoprotein (LDL) and high-density lipoprotein (HDL) in rat serum; ELISA was applied to detect the level of monocyte chemotactic protein (MCP-1) and hyper-sensitive C-reactive protein (hs-CRP) in rat serum; the level of oxidized low density lipoprotein (ox-LDL) and malondialdehyde (MDA) in rat serum were detected by spectrophotometry; HE staining was applied to find pathological changes in the common carotid artery of rats; Western blot was applied to detect the expression of Wnt3a, matrix metalloproteinase-9 (MMP-9) and β-catenin in rat common carotid artery. Results Compared with the control group, the level of TG, TC, LDL, MCP-1, hs-CRP, ox-LDL, protein expression of MDA, MMP-9, Wnt3a, β-catenin and total plaque area/total arterial area ratio increased, the HDL level decreased in model group (P＜0.05); compared with the model group, the level of TG, TC, LDL, MCP-1, hs-CRP, ox-LDL, MDA, expression of MMP-9, Wnt3a, β-catenin protein and total plaque area/total arterial area ratio in the low, medium, and high dose groups of Guanxinning tablets decreased, the HDL level increased. The effect of Guanxinning tablets was dose-dependent, and the change trend of corresponding indicators in the LiCl group was opposite to the above (P＜0.05); compared with the high dose group of Guanxinning tablets, the TG, TC, LDL, MCP-1, hs-CRP, ox-LDL, MDA levels, MMP-9, Wnt3a, β-catenin protein expression, and total plaque area/total arterial area ratio in the high dose+LiCl group of Guanxinning tablets increased, the HDL level decreased(P＜0.05). Conclusions Guanxinning tablet can inhibit the formation of atherosclerotic plaque in rats and the mechanismis potentially related to the regulation of Wnt/β-catenin pathway.

Key words: Guanxinning tablets, Wnt/β-catenin pathway, atherosclerosis, plaque, oxidative stress