Objective: To observe the effect of Yifei Tongluo formula on muscular arteries medial smooth muscle cell proliferation of hypoxia-induced pulmonary vascular remodeling in rat. Method: Sixty Wistar rats were divided into 5 groups:blank group

model group

experimental group(high-does

middle-does

low-does)

12 rats in each group. The trachea injection of 0.2 mL lipopolysaccharide (1 g·L-1)combined smoke method for four weeks was adopted to establish the model of chronic obstructive pulmonary disease(COPD)

and superposition of low oxygen(18%) two weeks establish pulmonary vascular remodeling(PVR) models in rats. The blank and model groups were perfused with saline

experimental group was perfused with Yifei Tongluo formula (30

20

10 g·kg-1). Samples were collected in 4

5

6 weeks respectively. The middle membrane thickness

vascular diameter and middle membrane area

vascular area were measured

then calculated the ratio of relative middle membrane thickness and area. Result: The ratio of relative middle membrane thickness and area in each point-in-time between the groups showed t as follows:model group> low-does group> middle-does> high-does> blank group

with significant difference. Conclusion: Yifei Tongluo formula can inhibit the muscular arteries medial smooth muscle cell proliferation of hypoxia-induced pulmonary vascular remodeling in rats.