Abstract: ObjectiveTo study the secretion of transforming growth factorβ₁ (TGF-β₁), vascular endothelial growth factor（VEGF）and plasminogen activator inhibitor-1（PAI-1）by fibroblasts(FB) and the influence of urokinase(UK) on the secretion. MethodsFibroblasts obtained from the pleura of fine male rats were cultured，purified and identified，and then were divided into control group 0, control group 1 and experimental group. There were 40 samples without fibroblasts in RPMI 1640 medium in control group 0 and 40 samples with many fibroblasts in RPMI 1640 medium in control group 1. 5000,10000,20000 and 30000IU/ml of urokinase were added into the 40 samples in four experimental groups, respectively. The samples each group were cultured for 24 hours, and then the level of TGF-β₁, VEGF and PAI-1 in cultured supernatant fluids were measured by enzyme linked immunosorbent assay(ELISA). ResultsTGF-β₁, VEGF and PAI-1 were not detected in control group 0. The concentration of TGF-β₁,VEGF and PAI-1 in control group 1 were (3135.205±390.975)pg/ml, (22.09±7.48)ng/ml, (1.8775±0.39) ng/ml, respectively. They decreased obviously in four experimental groups compared with control groups. ConclusionsPleural Fibroblasts could secrete TGF-β₁,VEGF and PAI-1.Urokinase could inhibit their secretion.

Key words: urinarg plasminogen actrvator, pleura, pleura, fibroblasts, transforming growth factorbeta, vascular endothelial growth faetor A, plasminogen activator inhibitor, rats, spraguedawley