OBJECTIVETo observe the anti-atherosclerotic effect and its possible mechanisms of Modified Zhenzhu Tiaozhi Capsule (MZTC) in rabbits.

METHODS50 rabbits were divided into five groups, i.e., the normal group, the model group, the simvastatin group (3 mg/kg), the high dose MZTC group (1.6 g crude drug/kg), and the low dose MZTC group (1.6 g crude drug/kg), respectively, ten in each group. The atherosclerosis (AS) model was established by feeding rabbits with high fat diet. Corresponding medicines were administrated on the basis of high fat diet for twelve successive weeks. Levels of blood lipids, serum superoxide dismutase (SOD), malondialdehyde (MDA), and nitric oxide (NO) were detected. The area of the aortic tunica intima plaque was determined. The pathological changes of the aorta were observed.

RESULTSCompared with the model group, serum levels of total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), MDA, and atherosclerotic index (AI) were significantly lowered in the MZTC groups (P<0.05, P<0.01), while serum levels of high-density lipoprotein cholesterol (HDL-C), SOD, and NO obviously increased (P<0.05, P<0.01). Serum levels of TC, TG, LDL-C, and in the MZTC groups were obviously higher than those of the simvastatin group (P<0.01), and there was insignificant difference in other indices. The ratio of the aortic tunica intima plaque percentage to the total tunica intima area was also markedly lower than that of the model group (P<0.05, P<0.01). Results under light microscope indicated the pathological changes of the aorta was obviously attenuated.

CONCLUSIONSMZTC could inhibit the formation and development of AS plaque. Its mechanism might be associated with regulating lipids metabolism, antioxidation, and improving endothelial functions.