OBJECTIVETo study the effects of puerarin on proliferation, apoptosis and Kv1.5 gene expression of rat pulmonary artery smooth muscle cells (PASMCs) induced by hypoxia.

METHODSThe rat PASMCs were divided into 5 groups: control group, hypoxia group, hypoxia plus puerarin (1 × 10(-5) mol/L) group, hypoxia plus puerarin (1 × 10(-4) mol/L) group and hypoxia plus puerarin (1 × 10(-3) mol/L) group, and cultured at 37°C for 24 h. The proliferation of rat PASMCs was detected by CCK-8 assay and flow cytometry, the activity of caspase-3 was measured with spectrophotometric method, Kv1.5 protein was detected by western blot, Kv1.5 mRNA was detected by real-time PCR.

RESULTSThe cell viability and proportion of synthesis phase in control group were 0.940 ± 0.045 and 9.67% ± 1.28%, which were significantly lower than those (1.296 ± 0.034 and 18.19% ± 1.19%) in hypoxia group (P < 0.05). The Caspase-3 activity, Kv 1.5 protein and Kv 1.5 mRNA in control group were 0.1073 ± 0.0113, 0.886 ± 0.038 and 0.0377 ± 0.0031, which were significantly higher than those (0.0664 ± 0.0049, 0.602 ± 0.064 and 0.0108 ± 0.0014) in hypoxia group (P < 0.05). As compared with hypoxia group, the cell viability and proportion of synthesis phase in 3 hypoxia plus puerarin groups significantly decreased, and the Caspase-3 activity, Kv 1.5 protein and Kv 1.5 mRNA in 3 hypoxia plus puerarin groups significantly enhanced (P < 0.05).

CONCLUSIONPuerarin could decrease the proliferation and increase the apoptosis induced by hypoxia in rat PASMCs, and the up-regulated expression of Kv1.5 gene may be the mechanism of puerarin effects.