Objective:To investigate the effect of Chaipu decoction on airway inflammation and extracellular signal-regulated kinase (ERK)/p38 mitogen-activated protein kinase (p38 MAPK) signal pathway in asthmatic rats. Method:A total of 60 SD rats were randomly divided into the blank control group

the model group

the low-dose Chaipu decoction group (0.75 g·kg-1)

the middle-dose Chaipu decoction group(1.5 g·kg-1)

the high-dose Chaipu decoction group (3.0 g·kg-1) and the dexamethasone group (0.005 g·kg-1). The rats were sensitized and challenged with ovalbumin (OVA) to establish the asthma model. The blank control group was given saline water; the model group was given saline water by gavage at 0.5 h before being challenged; the low dose group

the middle dose group and the high dose group were given the corresponding doses of Chaipu decoction by gavage at 0.5 h before being challenged; the Dexamethasone group was given dexamethasone by gavage at 0.5 h before being challenged; the drugs were given once every other day

for 28 days. The changes in the total and differential cell counts in bronchoalveolar lavage fluid (BALF) of different groups were observed. The activity of phosphorylated ERK (p-ERK) and phosphorylated p38 MAPK (p-p38 MAPK) in lung tissues were detected by enzyme linked immunosorbent assay (ELISA). ERK and p38 MAPK mRNA expressions in lung tissues were detected by Real-time PCR; expressions of ERK

p-ERK

p38 MAPK

and p-p38 MAPK in lung tissues were detected by Western blot; the changes in histopathology and inflammation scores were observed under optical microscope. Result:Compared with the blank control group

the changes in the total and differential cell counts in BALF

the activity of p-ERK and p-p38 MAPK

the expressions of ERK mRNA and p38 MAPK mRNA

the expressions of p-ERK and p-p38 MAPK in lung tissues were significantly increased in the model group (P<0.01); all of the above indexes in the low-dose group

the middle-dose group

the high-dose group and the dexamethasone group were significantly lower than those in the model group (P<0.05

P<0.01). Conclusion:Chaipu decoction could alliviate airway inflammation in asthmatic rats

and its mechanisms may be correlated with the inhibition of ERK/p38 MAPK signal pathway.