INHIBITORY EFFECTS OF BFGF, VEGF AND MINOXIDIL ON COLLAGEN-SYNTHESIS BY CULTURED HAIR DERMAL PAPILLA CELLS

Dermal papilla cells of rat vibrissa follicles cultivated in monolayer s and in three-dimensional collagen gels show a different morphology i n these culture systems, Dermal papilla cells cultured in lattices ten d to express morphological features resembling those seen in vivo. Qua ntification of total collagen by incorporation of H-3-proline in monol ayer cultures and in collagen lattices show that the amount of collage n found in dermal papilla cells is higher than that secreted. Moreover , collagen synthesis measured in lattices is reduced to about 50% of t hat found in monolayer cultures, The influence of growth factors on co llagen synthesis by hair dermal papilla cells was investigated, We stu died the effects of basic fibroblast growth factor (bFGF), vascular en dothelial growth factor (VEGF) and minoxidil on collagen synthesis in monolayers and in lattices, VEGF, bFGF and minoxidil significantly dec reased the total amount of collagen, In monolayer cultures, there was approximately a 30% inhibition of collagen production with 5 ng/ml bFG F, 0.1 ng/ml VEGF and 100 ng/ml minoxidil. However, in the lattices th is inhibition was reduced to about half, These results suggest that bo th culture substrate and growth factors influence collagen production by rat hair dermal papilla cells.