Effects of NHE-1 antisense RNA on apoptosis of pulmonary artery smooth muscle cells of rats in vitro

Objective To investigate the effects of NHE 1 antisense RNA on apoptosis of pulmonary artery smooth muscle cells(PASMC) in vitro.Methods Based on the sequence of NHE 1 mRNA,the DNA sequence encoding NHE 1 antisense RNA was obtained by PCR and subcloned into the multiple clone sites BamHI/EcoRI in retroviral vector pLXSN.Then the recombined plasmid was transfered into cultured PASMC.Expression of NHE 1 mRNA and cell cycle were detected by sqRT PCR and flow cytometric DNA analysis respectively.Intracellular pH(pHi) was measured using fluorescence dye BCECF AM.Cell apoptosis was observed with electron microscopy and terminal deoxynucleotidyl transferase medited dUTP nick end labeling (TUNEL) respectively.Results The NHE 1 mRNA expression and pHi values of cells transfected with the recombined plasmid decreased significantly than those cells transfected with pLXSN and nontransfected control.Meanwhile,the apoptosis rate of these cells increased significantly and electron microscopy also showed cell apoptosis of these cells.Conclusion NHE 1 inhibition can induce apoptosis of pulmonary artery smooth muscle cell by causing intracellular acidification.