Production of neuropeptide substance P by synovial fibroblasts from patients with rheumatoid arthritis and osteoarthritis

We examined the production of substance P (SP) in synovial fibroblasts deri ved from patients with rheumatoid arthritis (RA) and osteoarthritis (OA). I mmunoreactive SP was observed in non-stimulated RA fibroblasts. The express ion of beta -preprotachykinin-A (beta -PPT-A) mRNA was confirmed by reverse transcription-polymerase chain reaction analysis. SP contents in culture m edium were increased by treatment of RA fibroblasts with transforming growt h factor-beta (TG FP) (10 ng/ml). Levels of SP release were elevated at 12 h after TGF beta stimulation whereas the expression of beta -PPT-A mRNA was enhanced at 3 h. Furthermore, SP production in response to TGF beta was do se-dependently enhanced by basic fibroblast growth factor (bFGF). OA fibrob lasts also significantly released SP in the presence of TGF beta (10 ng/ml) plus bFGF (50 ng/ml). These results suggest that SP produced by synovial f ibroblasts may participate in joint diseases, (C) 2001 Elsevier Science ire land Ltd. All rights reserved.