Effect of valsartan on asthma mice's airway remodelling and CTGF expression

Objective To observe the influence of valstartan on airway remodelling and connective tissue growth factor(CTGF) expression in airway of mouse model of asthma.Methods Forty BALB/C mice were divided into 4 groups:normal control group,asthmatic model group, dexamethasone group(2 mg/kg),valstartan group(50 mg/kg).The mouse model of asthma was established by ovalbumin intraperitoneal injection and aerosolization.Dexamethasone group and valstartan group were given different treatments.The lung tissue slices were stained with Hematoxylin-eosin and Masson for analyzing the smooth muscle area and airway wall collagen area.The transcription level of CTGF was measured by reverse transcriptase-polymerase chain reaction to determine the level of its mRNA,and western bloting and immunohistochemistry were used to detect its protein expression and location.Results In these four groups,the area of bronchial smooth muscle and the area of collagen deposition were significantly higher in asthmatic model group than in control group(P 0.01),but remarkably lower in dexamethasone group and valstartan group than in model group(all P 0.01).The relative potency of mRNA and protein expression of model group was increased,as compared with control(P 0.01);dexamethasone group's and valstartan group's were decreased,as compared with model(P 0.01).The protein expression level of CTGF was positively correlated with the area of bronchial smooth muscle and with the area of collagen deposition(r=0.602,0.579 respectively,P 0.01).Conclusion The valsartan can inhibit airway remodelling in asthmatic mice and it may be correlated with the down regulation of CTGF in airway.