[Effects of hypoxia on the phenotype of porcine pulmonary arterial smooth muscle cells in vitro].

The effects of hypoxia on phenotype modulation of pulmonary artery smooth muscle cells (PASMC) was observed using cell culture and morphometry analysis. The results showed that the number of diploid cells and alpha-sm-actin of the hypoxic endothelial cell condition medium group (HECCM) was lower and the myofibrils were even less than that of the normal endothelial cell condition medium group (NECCM). On the contrary, the volume density of rough endothelial reticulum (RER) and mitochondria of the HECCM group were higher than that of the NECCM group. However, under hypoxic condition for 24 hours, the phenotype of cultured PASMCs remained unchanged. It suggests that the HECCM can induce phenotype modulation of PASMCs, may be mediated by the pulmonary artery endothelial cells (PAECs) which can secrete some cytokines affecting the PASMCs.