INTERACTION BETWEEN GROWTH-FACTORS AND KININS IN ARTERIAL SMOOTH-MUSCLE CELLS

Bradykinin receptors are present on vascular smooth muscle cells, howe ver, the regulation and biological function of these receptors is uncl ear. To address these questions the interaction between growth factors and kinins in cultured arterial smooth muscle cells has been examined . Based upon the data a hypothesis is presented that platelet-derived growth factor (PDGF) upregulates cell surface bradykinin B-2 receptors on arterial smooth muscle cells. The biological effect of the increas e in B-2 receptors is currently unclear but under certain conditions t hey may enhance mitogenesis. These mitogenic effects however, are stro ngly opposed by the effects of bradykinin acting via a B-1-type of rec eptor which mediates potent inhibition of growth factor-induced mitoge nesis.