Differential effects of PDGF and PDGF-BB on vascular smooth muscle cells.
Several biological effects of recombinant PDGF-BB and PDGF obtained from human platelets were examined with vascular smooth muscle cells. Although PDGF and PDGF-BB were equally potent mitogens for these cells, 5 fold higher levels of PDGF were required to displace 125I-PDGF-BB binding than PDGF-BB itself. Higher concentrations of PDGF relative to PDGF-BB were also required to stimulate the phosphorylation of a 163K protein in membrane preparations. PDGF-BB, but not PDGF, treatment of intact cells resulted in the phosphorylation on tyrosine residues of 168, 53, 48, and 45K proteins. The data suggest that PDGF and PDGF-BB stimulate smooth muscle cell mitogenesis by different mechanisms.
Reilly
C F
CF
Department of Pharmacology, Merck Sharp and Dohme Research Laboratories, West Point, PA 19486.
Broski
J E
JE
D000818:Animals; D001013:Aorta, Thoracic; D001667:Binding, Competitive; D001792:Blood Platelets / Q000032:analysis; D002417:Cattle; D004247:DNA / Q000096:biosynthesis; D006801:Humans; D007163:Immunosorbent Techniques; D046911:Macromolecular Substances; D008565:Membrane Proteins / Q000378:metabolism; D008970:Molecular Weight; D009131:Muscle, Smooth, Vascular / Q000378:metabolism*; D010766:Phosphorylation; D019000:Phosphotyrosine; D010982:Platelet-Derived Growth Factor / Q000378:metabolism / Q000494:pharmacology*; D011869:Radioligand Assay; D011994:Recombinant Proteins / Q000494:pharmacology*; D014443:Tyrosine / Q000031:analogs & derivatives / Q000378:metabolism
D046911:Macromolecular Substances; D008565:Membrane Proteins; D010982:Platelet-Derived Growth Factor; D011994:Recombinant Proteins; D019000:Phosphotyrosine; D014443:Tyrosine; D004247:DNA