Heterogeneity of smooth muscle cell populations cultured from pig coronary artery.
OBJECTIVE
Heterogeneous smooth muscle cell (SMC) populations have been described in the arteries of several species. We have investigated whether SMC heterogeneity is present in the porcine coronary artery, which is widely used as a model of restenosis.


RESULTS
By using 2 isolation methods, distinct medial populations were identified: spindle-shaped SMCs (S-SMCs) after enzymatic digestion, with a "hill-and-valley" growth pattern, and rhomboid SMCs (R-SMCs) after explantation, which grow as a monolayer. Moreover, the intimal thickening that was induced after stent implantation yielded a large proportion of R-SMCs. R-SMCs exhibited high proliferative and migratory activities and high urokinase activity and were poorly differentiated compared with S-SMCs. Heparin and transforming growth factor-beta2 inhibited proliferation and increased differentiation in both populations, whereas fibroblast growth factor-2 and platelet-derived growth factor-BB had the opposite effect. In addition, S-SMCs treated with fibroblast growth factor-2 or platelet-derived growth factor-BB or placed in coculture with coronary artery endothelial cells acquired a rhomboid phenotype. This change was reversible and was also observed with S-SMC clones, suggesting that it depends on phenotypic modulation rather than on selection.


CONCLUSIONS
Our results show that 2 distinct SMC subpopulations can be recovered from the pig coronary artery media. The study of these subpopulations will be useful for understanding the mechanisms of restenosis.
Department of Pathology, University of Geneva-CMU, University Hospital Geneva, Switzerland.
Hiroyuki
H
Hao
Patricia
P
Ropraz
Vitali
V
Verin
Edoardo
E
Camenzind
Antoine
A
Geinoz
Michael S
MS
Pepper
Giulio
G
Gabbiani
Marie-Luce
ML
Bochaton-Piallat
D000818:Animals; D000925:Anticoagulants / Q000494:pharmacology; D002465:Cell Movement / Q000235:genetics; D002478:Cells, Cultured; D003331:Coronary Vessels / Q000737:chemistry / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D004730:Endothelium, Vascular / Q000737:chemistry / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D006133:Growth Substances / Q000494:pharmacology; D006493:Heparin / Q000494:pharmacology; D009131:Muscle, Smooth, Vascular / Q000737:chemistry / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D010641:Phenotype; D013552:Swine; D017539:Tunica Intima / Q000737:chemistry / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D017540:Tunica Media / Q000737:chemistry / Q000166:cytology / Q000187:drug effects / Q000378:metabolism
D000925:Anticoagulants; D006133:Growth Substances; D006493:Heparin