[Effect of xiongshao capsule on lipid metabolism and platelet aggregation in experimental atherosclerosis rabbits].

OBJECTIVE: To study the effect and possible mechanism of xiongshao capsule (XSC) on lipid metabolism and platelet aggregation in experimental atherosclerotic (AS) rabbits. METHODS: Fractional AS rabbits model was established by denuding endothelium of abdominal aorta with 4F x Fogarty catheter, followed by high cholesterol feeding. Seventy model rabbits were equally randomized into 7 groups, namely, the 3 model groups (Group A, B and C) of different observation time (3 days, 2 weeks and 6 weeks respectively after operation); the single endothelium injury group (Group D, adopted denuding but fed with common diet); the 3 treatment groups treated respectively with probucol (Group E), low-dose and high-dose XSC (Group F and G) for 6 weeks. Besides, a control group (Group N) consisting of 10 rabbits underwent sham operation with normal feeding was set up. Animals were killed at different corresponding time points, heart blood was collected before killing for measurements of blood lipid indexes, including total cholesterol (TC), total triglyceride (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C). The 5 min maximum platelet aggregation rate (mPAGR) was measured with heart blood on the 3rd day after operation and at the terminal of experiment. RESULTS: (1) Indexes of blood lipids were unchanged in Group D and N (P > 0.05); TC and LDL-C in model rabbits began to rise significantly after being fed with high fat forage for 3 days; lipid indexes in Group A, B and C were significantly different to those in Group N, respectively (P < 0.05, P < 0.01); at the end of experiment TC and LDL-C were lower in Group G and E when compared with Group C; the ratio of LDL-C/HDT-C decreased in Group G, E and F, especially in Group G (P < 0.01); a bettering trend of HDL-C presented in Group G, but not in Group E; and reduction of atherosclerosis index (AI, calculated by TC/HDL-C) was found in Group G (P < 0.01), significant difference was shown as compared with that in Group C and E (P < 0.05). (2) The 3rd day mPAGR raised in Group A, B, C and D, showing significant difference as compared with that in Group N (P < 0.01), whereas the index in Group E, F and especially in G was lower significantly than that in Group C (P < 0.05). mPAGR in the 3 treatment groups at the terminal of experiment was lower than that in Group C (P < 0.05, P < 0.01), and the most effective lowering was shown in Group G. CONCLUSION: XSC could reduce the levels of TC, LDL-C and AI in AS model rabbits, also inhibit platelet aggregation at early stage and 6 weeks after endothelium injury, which might be one of the possible acting mechanisms of XSC in preventing AS.