Objective To explore possible action mechanism of Yanghe Pingchuan Granule（ 阳和平喘颗粒

YHPCG） in treating bronchial asthma. Methods Totally 90 SD rats were randomly divided into normal group

asthma model group

dexamethasone group and low

medium and high dose groups of YHPCG

with 15 rats in each group. The researchers used methods of intraperitoneal injection of ovum albumin（ OVA） to sensitization and aerosol inhalation to build models of asthma rat

and used intraperitoneal injection of hydrocortisone to replicate models of kidney-yang deficiency. On the 28 th day

the low

medium and high dose groups of YHPCG were respectively given intragastric administration of 1. 62

3. 24

and 6. 48 g /（ kg · d）. The dexamethasone group was given intragastric administration of 0. 5 mg /（ kg·d）

once a day for 2 weeks. The normal group and the asthma model group were respectively given intragastric administration of the same amount of normal saline. The researchers respectively used HE staining and PAS staining to detect pathology change of lung tissue and secretion situation of airway mucins. And they used real-time PCR method to detect the expression level of mucoprotein 5AC（ MUC5AC） and mucoprotein 5B（ MUC5B） mRNA in lung tissue. They also used ELISA method to detect level changes about bronchoalveolar lavage fluid MUC5 AC and MUC5 B. Results Compared with the normal group

lung tissue in the asthma model group showed extensive infiltration of inflammatory cells

airway stenosis

enlargement of alveolar space

significantly increased secretion of airway mucoprotein and increased expression levels of MUC5 AC

MUC5B protein and mRNA（ P < 0. 01）. Compared with the asthma model group

in the low

medium and high dose groups of YHPCG

morphology structure of lung tissue of those rats obviously improved and the size of the airway lumen obviously recovered

at the same time

expression level of MUC5 AC

MUC5B protein and mRNA decreased（ P < 0. 01）. Conclusion YHPCG may achieve the effects to treat bronchial asthma by reducing infiltration of inflammatory cell and reducing secretion of airway mucoprotein.