Proteinase-activated receptors and the pathophysiology of pulmonary fibrosis

Interest in the role of proteinase-activated receptors (PARs) in the pathogenesis of fibrotic lung disease was fuelled by two central observations: first, the recognition that the coagulation cascade is activated in a number of these disorders; and second, the long-standing observation that thrombin, a principal regulator of coagulation, is a potent mitogen for fibroblasts, the key cell type responsible for the production of interstitial collagens in the fibrotic lung. This article will briefly review this evidence and focus on recent studies suggesting an important role for PAR(1)-mediated cellular responses in the pathophysiology of lung fibrosis. (C) 2003 Wiley-Liss, Inc.