Effect Of Liopopolysaccharide On Pulmonary Vascular Endothelial Cells And Its Mechanism In Neonatal Mice

Objective: To isolate and culture the pulmonary vascular endothelial cells of neonatal mice,and to explore its possible mechanism.Methods: The identified cells were randomly divided into blank control group and LPS group.The cells in the LPS group were treated with 10 ug/ml LPS,and the control group was not treated;cell samples were collected at 0h,6h,12 h,24h,and 48 h for detection.The migration of pulmonary vascular endothelial cells was observed by the scratch test;the mRNA expression of Chemokine and inflammatory cytokines in the lung vascular endothelial cells were determined by real-time PCR(RT-PCR);the protein level of P65,VEGF and VEGFR-2 were determined by Western blot.Results: The pulmonary vascular endothelial cells were exhibited as polygon and presented typical cobblestone-like morphology after fusion to monolayer with contact inhibition.Immunofluorescence staining revealed that the expression of CD31 and factor ?-related antigen was positive.The migration of LPS group cells in the scratch test was higher than that of the control group at 12h(P<0.001).The mRNA expression of inflammatory factors IL-1?,TNF-? and chemokines MIP-1? and MCP-1 secreted by LPS group was significantly higher than that control group by real-time PCR(P<0.001);the protein expression of NF-?B-related protein P65 activity increased(P<0.05),the expression of VEGFR2 protein on the surface of pulmonary vascular endothelium was significantly decreased(P<0.001);the vascular endothelial growth factor(VEGF)in LPS group was decreased.Conclusion: The inflammatory response induced by lipopolysaccharide affects the development of pulmonary vascular endothelial cells,and its mechanism may be related to the activation of NF-?B pathway,the induction of inflammatory factors,the increase of chemokine expression and the decrease of VEGF/VEGFR2 expression.