RESUMO
<p><b>OBJECTIVE</b>To investigate the potential cell sources of neointimal cells in autologous vein graft in rat model.</p><p><b>METHODS</b>Vein graft neointimal cell origins were investigated using a model of vein-to-artery interposition modal. Slides were stained with hematoxylin and eosin, immunohistochemical staining was also performed with primary antibodies alpha-smooth actin or CD34.</p><p><b>RESULTS</b>Neointimal thickening was greater at the proximal ends (65.2 +/- 4.6) microm and, to a lesser extent, distal ends (64.7 +/- 5.3) microm, in comparison to the middle of the graft (63.5 +/- 5.6) microm. Vein-originating cells survived and make a contribution to neointimal formation within the vein graft, mostly adjacent to the lumen, suggesting an intimate association with endothelial cells, donor arterial smooth muscle cells or circulating progenitor cells.</p><p><b>CONCLUSIONS</b>Vein graft neointimal cells arise predominantly from vein-derived endothelial cells, donor arteria smooth muscle cells or circulating progenitor cells. It suggests clinical relevance of stenosis-inhibiting therapies directed at the vein graft or early system pharmacologic administration.</p>