BASIC FIBROBLAST GROWTH-FACTOR IN THE EXTRACELLULAR-MATRIX SUPPRESSESCOLLAGEN-SYNTHESIS AND TYPE-III PROCOLLAGEN MESSENGER-RNA LEVELS IN ARTERIAL SMOOTH-MUSCLE CELL-CULTURES
A. Majors et La. Ehrhart, BASIC FIBROBLAST GROWTH-FACTOR IN THE EXTRACELLULAR-MATRIX SUPPRESSESCOLLAGEN-SYNTHESIS AND TYPE-III PROCOLLAGEN MESSENGER-RNA LEVELS IN ARTERIAL SMOOTH-MUSCLE CELL-CULTURES, Arteriosclerosis and thrombosis, 13(5), 1993, pp. 680-686
To determine the effects of an intact extracellular matrix on collagen
synthesis, arterial smooth muscle cells (SMCs) were plated sparsely o
n a cell-free, SMC-derived matrix and examined the following day. Coll
agen synthesis during a 5-hour incubation by cells on the matrix was r
educed to 67% of the control values obtained from cultures on plastic.
Total protein synthesis was unaffected. Treatment of the matrix with
heparitinase to remove basic fibroblast growth factor (bFGF) before se
eding the SMCs abolished the inhibitory effect of the matrix on collag
en synthesis. The inhibitory effect was also eliminated by treating th
e matrix with a neutralizing polyclonal antibody directed against bFGF
. Collagen synthesis by SMC cultures grown in wells coated with purifi
ed bFGF was only 61% that of control cultures, whereas total protein s
ynthesis remained unchanged. Slot-blot analysis revealed that the rela
tive message level for alpha1(III) procollagen was reduced in cultures
grown on the preexisting matrix or on plastic precoated with bFGF, wh
ereas the alpha1(I) procollagen message was unaffected. These results
demonstrate the ability of the extracellular matrix to modulate the sy
nthesis of collagen by arterial SMCs and indicate that bFGF in the mat
rix is responsible for these effects.