关键词: 低氧, Apelin-APJ系统, 肺血管内皮细胞

Abstract:

Objective To investigate the changes of the expression of apelin-APJ system in the injury of pulmonary vascular endothelial cells (PVECs) under hypoxia conditions, and to clarify the role of apelin in the cell proliferation. Methods The in vitro cultured rat PVECs were divided into control group, hypoxia 6 h group, hypoxia 12 h group,hypoxia 24 h group,hypoxia 48 h group,hypoxia 24 h + apelin group and apelin group. The proliferation rates of PVECs in every group were detected by MTT assay. The in vitro cultured rat PVECs were divided into normal control group,hypoxia 6 h group,hypaxia 12 h group and hypoxia 24 h group.The expression of apelin in the cells were observed by immunofluorescence staining. The expression levels of apelin-APJ protein were measured by Western blotting method. Results Compared with normal control group, the proliferation rates of the PVECs in hypoxia 6 h,12h groups and apelin group had no change(P>0.05), but the proliferation rates of the PVECs in hypoxia 24 h and 48 h groups were decreased significantly(P<0.05 or P<0.01). Compared with normal control group, the immunofluorescence expression of apelin in the PVECs in hypoxia 6 h group had no obvious change(P>0.05), but the expression of apelin in the PVECs in hypoxia 12 h and 24 h groups were decreased (P<0.01). Compared with normal control group, the expression levels of apelin protein in the PVECs in hypoxia 6 h, 24 h and 48 h groups were decreased(P<0.01), but the protein expression of APJ in the PVECs had no significant changes(P>0.05). Conclusion Hypoxia may injury the PVECs through inhibiting the apelin expression, and exogenous apelin can protect the injure of PVECs induced by hypoxia.

Key words: hypoxia, apelin-APJ, pulmonary vascular endothelial cells