RESUMO
<p><b>OBJECTIVE</b>Platelet-derived growth factor (PDGF) plays an important role during the pathophysiological changes in vascular remodeling. The study aimed to investigate the effect of truncated PDGF-alpha receptor on apoptosis and expression of c-sis mRNA of pulmonary artery smooth muscle cells (VSMCs).</p><p><b>METHODS</b>Tissue mass culture was done to get vascular smooth muscle cells of pulmonary artery in newborn pigs. Two methods were used to interfere VSMCs: adding adenoviral recombined body (Ad5CMV-PalphaRtr, ACP) with three different concentrations of truncated PDGF-alpha receptor into the cultures, or adding three concentrations of PDGF-BB after the treatment with mid-concentration of ACP. VSMC apoptosis, cellular cycle and expression of c-sis were observed using flow-cytometry, and the expression of c-sis mRNA was detected by reverse transcription polymerase chain reaction (RT-PCR).</p><p><b>RESULTS</b>ACP with mid- to- high concentrations could restrain the proliferation of VSMCs apparently with the increase of G(0)/G(1) cells. The apoptotic rate presented an ascending tendency. The differences among the groups were of statistically significant. Affected by mid- concentration of ACP, PDGF-BB did not exhibit a significantly accelerating effect on the changes of cellular cycle and VSMC apoptosis. The expression of c-sis mRNA was up-regulated under the effect of ACP. Affected by mid-concentration of ACP and PDGF-BB, c-sis mRNA expressed was down-regulated.</p><p><b>CONCLUSION</b>Mid- to- high concentration of ACP is a powerful inhibitor of cellular proliferation for pulmonary artery VSMCs. It can significantly increase cells in number in G(0)/G(1) phase, apoptosis and c-sis mRNA expression.</p>