Objective: To study the effect of Jiangzhi Mixture (IM) on low density lipoprotein (LDL) oxidative susceptibility and low density lipoprotein receptor (LDL-R) gene expression in rats with hyperlipidemia

and elucidate the possible mechanism of IM regulating blood lipid. Method: Sixty Wistar male rats were randomly divided into normal group

model group

simvastatin and IM high

middle

low dose groups

10 rats in each group. The rats in normal control group were fed with basal diet

the rats in the other groups were fed with a high fat diet to establish hyperlipidemia rat models

and during modeling the drugs were used for prevention. Physiological saline were given to the rats in control group and model group

simvastatin group rats were given 7.2×10-4g·kg-1 simvastatin suspension solution

and Jiangzhi Mixture low

middle

and high dose groups were intragastrically given 0.25

0.5

1 g·kg-1 decoction

respectively

10 mL·kg-1

once a day for 10 weeks

during making model. After 10 weeks

according to the method of abstracting eyeball blood

the blood lipid spectrum of each individual animal in various groups were measured with full automatic biochemical analyzer. After separation of LDL

its susceptibility to oxidation was determinated in vitro. According to the method of Trizol extracting liver RNA of rats

LDL-R mRNA expression was determinated by RT-PCR. Result: Compared with model group

the cholesterol (TC)

triglycerides (TG)

low density lipoprotein chelesterol(LDL-C)

and apolipoprotein B (Apo B) levels in Jiangzhi Mixture groups were regulated and inhibited; the high density lipoprotein chelesterol(HDL-C)

apolipoprotein A (Apo A) levels and Apo A/Apo B ratio were increased

meanwhile the differences were statistically significant (P<0.05 or P<0.01); Compared with the model group

the maximum rate of oxidation time (Tmax) and LDL oxidation lag time (lag time) were significantly prolonged

and the relative expression levels of liver LDL-R mRNA were significantly elevated in all Jiangzhi mixture dose groups

and the differences were statistically significant (P<0.05 or P<0.01). Conclusion: Jiangzhi Mixture can modulate blood lipid metabolism in experimental hyperlipidemia rats models

reduce LDL susceptibility to oxidation of hyperlipidemia rat significantly

and induce liver tissue LDL-R mRNA expression of hyperlipidemia rat

and have good adjusting effect on lipid abnormalities.