Effect of Carvedilol on the expression of inflammatory factor in myocardial tissue of the mice with myocardial fibrosis induced by coxsachievirus B3 / 中华实用儿科临床杂志

ABSTRACT

Objective To study the role of transforming growth factor-β1 (TGF-β1),connective tissue growth factor (CTGF)and endothelin-1 (ET-1) in myocardial tissues of the mice with myocardial fibrosis induced by coxsachievirus B3 (CVB3) and the effect of Carvedilol intervention for it in acute stage and chronic phase of viral myocarditis.Methods Forty male BALB/c mice were randomly divided into 4 groups (10 cases in each group)control group,model group,Carvedilol acute phase intervention group,the chronic phase intervention group.Mice in model group and Carvedilol intervention groups were inoculated with CVB3 (100TCID50/0.1 mL) by peritoneal injection fortnightly.Mice in control group were given normal saline(NS) instead equivalently.Mice were poured Carvedilol (10 mg/kg per day for 2 weeks) from the second day in acute phase intervention group and from the fourth week in the chronic phase intervention group,while mice of control group and model group were poured with equivalent NS instead.At the end of 6 weeks,mice were sacrificed.Heart weight index (HWI) was determined.The collagen volume fraction (CVF) of left ventricular myocardial tissue were examined after Masson staining.Expressions of ET-1,TGF-β1 and CTGF were detected by enzyme linked immunosorbent assay and immunohistochemistry staining respectively; the mRNA expression was tested by reverse transcription-polymerase chain reaction.Results Compared with the control group,HWI and CVF of model group increased significantly(all P ＜ 0.01),those of the intervention groups decreased than those of the model group(all P ＜ 0.01),and in the acute phase those of the intervention group were significantly lower than those in chronic phase intervention group(all P ＜ 0.05).The expressions of TGF-β1,CTGF,ET-1 and their mRNA in model group were increased significantly than those in the control group(all P ＜0.01),and were decreased in acute and the chronic phase intervention group than those in model group(all P ＜0.01),while those were significantly lower in acute phase intervention group than those in chronic phase intervention group (all P ＜ 0.01).Conclusions TGF-β1,CTGF and ET-1 may be involved in myocardial fibrosis induced by CVB3.Compared with the chronic phase intervention,the acute phase intervention of Carvedilol can reduce myocardial fibrosis more efficiently by down-regulating the excessive expression of inflammatory factors.