Objective: To study the action mechanism of Xuanfei Pingchuan capsules in treating chronic obstructive pulmonary disease (COPD). Method: Totally 60 healthy SD rats were selected. Except for 10 rats in the normal group

all of the remaining rats were included in the COPD model by means of smoking mold and intratracheal injection with lipopolysaccharide. After the successful modeling

they were randomly divided into low-dose

middle-dose and high-dose Xuanfei Pingchuan capsules groups (0.38

0.75

1.5 g·kg-1)

the model group

and the positive drug group (dexamethasone

0.09 mg·kg-1). The normal group and the model group were given distilled water

ig

the positive drug group was given Dexamethasone suspension

ig

while the remaining treatment groups were given Xuanfei Pingchuan capsules suspension

ig

for 30 day

once a day. After the final ig

general conditions of the rats were observed. The content of tumor necrosis factor-α(TNF-α)

vascular endothelial growth factor (VEGF)

interleukin-8(IL-8) and interleukin-1β(IL-1β) in serum were detected by ELISA. Western blot was used to detect the expression of platelet deriwed growth factor-B(PDGF-B)

and the leukocyte count and the category of leukocytes in the bronchoalveolar lavage fluid (BALF) of rats. HE staining was adopted for the histopathological examination. Result: Compared with the normal group

in the model group

the content of TNF-α

IL-8 and IL-1β in serum was higher (P<0.01)

the content of VEGF was lower (P<0.01)

the PDGF-B content in lung tissues was higher

the total number of leukocytes in bronchoalveolar lavage fluid was higher (P<0.01)

the percentages of neutrogherphils

lymphocytes and alveolar macrophages were higher (P < 0.05

P < 0.01). Compared to the model group

in the Xuanfei Pingchuan capsules groups

the content of TNF-α

IL-8

IL-1β were lower (P < 0.05

P < 0.01)

the content of VEGF was significantly higher

PDGF-B in lung issues was remarkably lower (P < 0.05

P < 0.01)

the percentages of neutrogherphils

lymphocytes and alveolar macrophages were notably lower (P<0.05); compared with the dexamethasone group and model group

Xuanfei Pingchuan capsules high-dose group showed significant decrease in the total number of leukocytes in bronchoalveolar lavage fluid (P < 0.05

P < 0.01). Conclusion: Xuanfei Pingchuan capsules can lower the content of TNF-α

IL-8

IL-1β in the CORD rat serum and the PDGF-B in lung issues

and increase the VEGF in serum. In high-dose group

the number of BALF leukocytes was reduced. The action mechanism is probably related to reducing the generation and release of inflammatory mediators

exerting the anti-inflammatory effect

relieving airway mucus secretion epidermis

and inhibiting airway remodeling.