The expression of 5-HTR2B、E-cad、α-SMA in the pulmonary fibrosis in rats

Abstract

To observe the expression of 5-Hydroxytryptamine 2B receptor (5-HTR2B)、E-cadherin (E-cad)、alpha-smooth muscle actin(α-SMA) in the bleomycin -induced pulmonary fibrosis tissue of rats. Forty-five healthy male SD rats were randomly di-vided into control group,bleomycin group and bleomycin+prednisone group(n=15). Five rats in each group randomly sacrificed at the 7th、the 14th and the 28th day after eastablishing models. The lung tissue was observed by microscope in HE and Masson staining. Lung hydroxypro-line (HYP) content was evaluated. The expression of protein and mRNA of 5-HTR2B, E-cad and α-SMA were analyzed by immunohistoche-mistry and/or RT-PCR. A dynamic changes from alveolitis to pulmonary fibrosis could be observed in the slices by HE and Masson staining. The experimental results by immunohistochemistry and RT-PCR showed that the protein and mRNA expression of 5-HTR2B and a-SMA enhanced rat pulmonary fibrosis (P<0.05) and reached the highest at the 28th day; the corresponding protein and mRNA expression of E-cad reduced (P<0.05), and reduced to the lowest value at the 28th day. Compared with bleomycin group, the corresponding mRNA and protein expression of 5-HTR2B and a-SMA in bleomycin+prednisone group had decreased (P<0.05); however, the corresponding mRNA and protein expression of E-cad had increased(P<0.05). 5-HTR2B is involved in the pathogenesis of pulmonary fibrosis throught epithelial-mesenchymal transition (EMT).