The effect of transforming growth factor β_1 on the expression of collagen type III in the bladder detrusor

Objective To explore the relationship between transforming growth factorβ 1(TGF-β 1) and the expression of detrusor collagen.Methods Detrusor smooth muscle of rats was cut into small pieces under sterile conditions. Suspensions were cultured in medium with 15% fetal calf serum, 2.0g/L NaHCO 3, 100U/ml penicillin and 0.1mg/ml streptomycin. Cells were grown at 37℃ in an incubator with a humidified atmosphere of 5% CO 2 in air. When cultures reached a confluence of about 80%, cells were suspended by incubating them with trypsin. They were maintained and expanded with the same culture medium. TGF-β 1 of 0ng/ml, 5ng/ml, 10ng/ml and TGF-β 1 antibody of 0ng/ml, 5ng/ml, 10ng/ml were added to medium for 24 hours, respectively. Cells were collected for in-situ hybridization to demonstrate the expression of type Ⅲ collagen.Results The positive staining for type Ⅲ collagen was significantly increased with the concentration of TGF-β 1 increase. When TGF-β 1 concentration was increased from 0ng/ml to 10ng/ml, the light density value was increased from 0.425 to 0.642. However, the positive staining for type Ⅲ collagen was decreased with TGF-β 1 antibody concentration increase. The light density values were decreased from 0.425 to 0.221 when concentration of TGF-β 1 antibody was increased from 0ng/ml to 10ng/ml.Conclusions TGF-β 1 has an effect of accelerating deposition of collagen in bladder detrusor.