ObjectiveTo explore the expressions of prostaglandin F2α receptor (PTGFR) and cyclooxygenase-2 (COX-2) in tissues of benign bile duct scar and their significances, and investigate the regulating effect of transforming growth factor-β1 (TGF-β1) on the expression of PTGFR in human bile duct fibroblasts cultured in vitro. MethodsThe samples of common bile duct (CBD) scars were collected from 18 patients with benign bile duct scar stricture and 6 cases of normal CBD tissues from liver transplantation donor were collected as control. The expressions of PTGFR and COX-2 were detected by immunohistochemical strept-avidin-biotin complex (SABC) method. Semiquantitative RT-PCR and ELISA methods were used to detect the mRNA and protein levels of PTGFR in bile duct fibroblasts which were effected by TGF-β1 with different concentrations (0, 10, 20, and 30 ng/ml) for 24 h. ResultsThe positive rates of PTGFR and COX-2 were 88.9% (16/18) and 83.3% (15/18) in tissues of benigh CBD scar and 33.3% (2/6) and 0 (0/6) in normal CBD tissues (Plt;0.05). The expressions of the PTGFR mRNA and protein levels became upregulated when the concentrations of the TGF-β1 became higher in human bile duct fibroblasts (Plt;0.05). And the effect was concentration dependant to some extent. ConclusionsThe high expressions of PTGFR and COX-2 play important roles in the process of benign bile duct stricture formation. TGF-β1 is able to induce higher expressions of PTGFR mRNA level and the PTGFR protein level in a concentration dependent manner, and regulate the formation of benign bile duct stricture.