[Hypoxia enhances proliferation and migration of mouse pulmonary artery smooth muscle cells in vitro].

Objective To establish and improve a primary culture method of mouse pulmonary artery smooth muscle cells (PASMCs), and explore the effects of different hypoxic conditions on the proliferation, migration, and apoptosis of PASMCs. Methods Under sterile conditions, pulmonary arteries were isolated from male mice and PASMCs were obtained using an improved method of tissue piece inoculation through digesting with trypsin. Cell morphology was observed under an inverted phase-contrast microscope, and cell growth curve was plotted by cell counting. Immunofluorescence staining of α-smooth muscle actin (α-SMA) was used to assess the cell type and purity of PASMCs. The effect of different oxygen concentrations on the proliferation of PASMCs was detected by CCK-8 assay. Under hypoxia, the migration ability of PASMCs was detected by scratch wound assay, and the expression of BAX protein was detected by Western blot analysis. Results The cells tended to be long spindle and grew in the typical "peak-valley" mode. Cells were confluent after 9 days and the growth curve presented with a sigmoidal shape. The positive expression rate of α-SMA was 96%. Compared with the normoxic group, the proliferation and migration of PASMCs significantly increased under hypoxia at all time points, and the cell proliferation and migration was the most significant under the condition of 10 mL/L oxygen content. Moreover, BAX protein level of the cells was significantly reduced under hypoxia in a time-dependent manner. Conclusion The primary PASMCs with high purity and activity can be obtained by enzyme digestion and tissue mass adherent method. PASMCs exhibit higher proliferation, increased migration, and declined apoptosis under 10 mL/L oxygen concentration.