A subpopulation of smooth muscle cells in injured rat arteries expresses platelet-derived growth factor-B chain mRNA.
Proliferation of smooth muscle cells (SMCs) and formation of a neointima are characteristics of the response of rat carotid arteries to balloon injury. Rat platelet-derived growth factor (PDGF)-B was cloned, thus allowing us to use species-specific probes to carry out in situ hybridization on the surface of injured arteries. A distinct population of luminal SMCs (7% to 10%) in the developing neointima expressed PDGF-B mRNA, but very few luminal SMCs still expressed PDGF-B (0.5%) when the lesion had stopped growing. Primary SMC cultures revealed expression of PDGF-B mRNA in 1.6% of SMCs derived from normal tunica media and in 11% of SMCs derived from the neointima. These data demonstrate that SMCs in the injured vessel wall are heterogeneous with regard to PDGF-B expression and that subculturing of these cells may give rise to cultures that are either positive or negative for PDGF-B expression. Furthermore, with abundant expression of the PDGF receptor beta-subunit expressed by intimal SMCs, our findings provide evidence that PDGF-B synthesized by these cells may be involved in intimal lesion formation via a paracrine or autocrine mechanism.
Lindner
V
V
University of Washington, Department of Pathology, Seattle 98195, USA.
Giachelli
C M
CM
Schwartz
S M
SM
Reidy
M A
MA
D000595:Amino Acid Sequence; D000800:Angioplasty, Balloon / Q000009:adverse effects; D000818:Animals; D001483:Base Sequence; D002339:Carotid Arteries / Q000166:cytology; D020212:Carotid Artery Injuries; D002478:Cells, Cultured; D003001:Cloning, Molecular; D015342:DNA Probes; D015870:Gene Expression; D017403:In Situ Hybridization; D008297:Male; D008969:Molecular Sequence Data; D009131:Muscle, Smooth, Vascular / Q000166:cytology*; D010982:Platelet-Derived Growth Factor / Q000235:genetics*; D011153:Population; D011505:Protein-Tyrosine Kinases / Q000235:genetics*; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D020574:Proto-Oncogene Proteins c-sis; D012333:RNA, Messenger / Q000235:genetics*; D051381:Rats; D017207:Rats, Sprague-Dawley; D017479:Receptors, Platelet-Derived Growth Factor
D015342:DNA Probes; D010982:Platelet-Derived Growth Factor; D011518:Proto-Oncogene Proteins; D020574:Proto-Oncogene Proteins c-sis; D012333:RNA, Messenger; D011505:Protein-Tyrosine Kinases; D017479:Receptors, Platelet-Derived Growth Factor