ALTERED FIBRONECTIN-DEPENDENT CELL-ADHESION BY PDGF ACCOMPANIES PHENOTYPIC MODULATION OF VASCULAR SMOOTH-MUSCLE CELLS

PDGF promotes growth of smooth muscle cells (SMCs) and induces morphological changes. We investigated the effects of PDGF on cell-matrix adhesion of SMCs. PDGF reorganized integrin distribution as well as actin filament structure. PDGF-treated cells attached more loosely to fibronectin than non-treated cells. Decreased expression of α-actin by PDGF was antagonized by coating culture dishes with fibronectin but not with vitronectin and laminin. The inhibition of cell adhesion by GRGDSP oligopeptide and anti-fibronectin receptor antibody led to the reduction in α-actin expression. These results suggest that PDGF may modulate phenotype of SMCs by altering fibronectin-integrin interaction. © 1993 Academic Press, Inc.