[The effect of carbon monoxide on the proliferation of PASMCs under hypoxia and the mechanism].

AIM AND METHODS: MTT colorimetric assay, in situ hybridization and immunocytochemistry were performed to investigate the effect of endogenous and exogenous CO on the proliferation of PASMCs and the expression of PDGF-B and protooncogene bcl-2, P53 (mutant type) in PASMCs, in order to elucidate the mechanism by which CO suppressed the proliferation of PASMC in hypoxic environment. RESULTS: The results of in situ hybridization of PDGF-B mRNA and immunocytochemical staining of PDGF-B were negative. Hypoxia could upregulate the expression of Bcl-2, mutant P53 protein in comparison with the control group (P < 0.01). Compared with the hypoxic group, the expression of Bcl-2 and mutant P53 were decreased after treated with hemin or CO, but increased after treated with hemoglobin (P < 0.01). CONCLUSION: CO could suppress the expression of oncogene bcl-2 and mutant P53. This partially explained how CO suppressed the proliferation of PASMCs in hypoxic environment.