Effects of Gax gene transfection on proto-oncogene expression and proliferation of PASMCs in rats under hypoxia conditions

AIM:To explore the effects of Gax gene transfection on expressions of c-fos and c-jun mRNA and proliferation of pulmonary arterial smooth muscle cells (PASMCs) in rat under hypoxia. METHODS: PASMCs were transfected with Gax gene by Ad-Gax. Under normal oxygentention (21% O2) or hypoxia (2.5% O2) for 12 h condition, expressions of Gax mRNA and protein in PASMCs were detected by RT-PCR and immunocytochemistry. The expressions of c-fos and c-jun mRNA were evaluated by RT-PCR. [3H]-TdR incorporation was used to measure the PASMCs proliferation. RESULTS: The Gax overexpression in transfection group was confirmed by RT-PCR and immunocytochemistry. Under normal oxygentention or hypoxia, the c-fos and c-jun mRNA levels in transfection group were lower than those in the non-transfection group, respectively (P0.05). [3H]-TdR incorporation in the transfection group was lower than that in non-transfection group (P0.05, P0.01). CONCLUSION: Gax overexpression might inhibit the PASMCs proliferation induced by hypoxia through downregulating the expressions of c-fos and c-jun.