Objective: To investigate the influence and possible anti-atherosclerotic mechanism.of serum contained Buyang Huanwu decoction on the expression of toll-like receptor 4(TLR4) and its downstream signal transduction pathway and LOX-1 in human umbilical vein enddhelial cells(HUVECs). Method: Twenty New Zealand rabbits were divided into 4 groups in random:the normal control group

the high dosage group

the middle dosage group

and the low dosage group of Buyang Huanwu decoction

with 5 rabbits in each group. Each group was ig given normal saline and Buyang Huanwu decoction at dosage of 13.2

6.6

3.3 g·kg-1

respectively everyday. In the 7th day

blood was collected from lefe ventricle in 2 h after administration

and then the serum was separated. HUVECs was cultured in vitro and stimulated with lipopolysaccharide(LPS) 1 mg·L-1 for 2 h

then treated separately with the serum contained different concentrations of Buyang Huanwu decoction for 24 h

finally the expression of TLR4

MyD88

TRAF-6

TRAM

TRIF

NF-κB and LOX-1 mRNA was measured with real-time PCR. Western blotting method was used to analyze the expression of TLR4

MyD88

TRAF-6 and LOX-1 protein. Result: LPS enhanced the expression of TLR4

MyD88

TRAF-6

TRAM

TRIF

NF-κB and LOX-1(vs normal control group

P<0.01). The serum contained Buyang Huanwu decoction decreased the high expression of TLR4

MyD88

TRAF-6

NF-κB and LOX-1 (vs model group

P<0.05)

which was stimulated by LPS. Conclusion: The serum contained Buyang Huanwu decoction can block the high expression of TLR4 and its downstream signal transduction pathway and the high expression of LOX-1

which may be the mechanism of anti-artherosclerosis and inhibition of inflammatory reaction.