ABSTRACT
AIM:To investigate the RELMα/FIZZ1 signaling pathway on the regulation of the Ca 2+/CaM sig-naling pathway in the mouse aortic smooth muscle cells MOVAS and on the formation of blood vessels in the mouse aortic endothelial cells(MAEC).METHODS:The MAEC cultured in vitro were divided into pGSadeno-HK group,pGSadeno-RELMα/FIZZ1 group,pGSadeno-shRNA control group and pGSadeno-shRNA RELMα/FIZZ1 group.MTT assay was used to detect the viability of the MAEC.The formation of stroma tubes was observed for determining angiogenesis.The MOVAS cells cultured in vitro were also divided into pGSadeno-HK group,pGSadeno-RELMα/FIZZ1 group,pGSadeno-shRNA con-trol group and pGSadeno-shRNA RELMα/FIZZ1 group.The viability of MOVAS cells was measured by MTT assay.Fluo-3 AM fluorescence probe was used to detect intracellular Ca 2+concentration.The expression of calmodulin(CaM)and my-osin light chain kinase(MLCK)at mRNA and protein levels was determined by real-time PCR and Western blot.RE-SULTS:Over-expression of RELMα/FIZZ1 significantly promoted the viability of the MAEC.The number of lumen forma-tion was increased significantly(P<0.05).Knockdown of the RELM α/FIZZ1 expression inhibited the viability and lumen formation of MAEC(P <0.05).Over-expression of RELMα/FIZZ1 significantly promoted the viability of the MOVAS cells,enhanced the mean fluorescence intensity of intracellular Ca 2+,and the expression of CaM and MLCK at mRNA and protein levels was significantly increased.Knockdown of the RELMα/FIZZ1 expression significantly inhibited the viability of the MOVAS cells,the mean fluorescence intensity of Ca 2+was decreased, the expression of CaM and MLCK at mRNA and protein levels was decreased significantly(P<0.05).CONCLUSION:RELMα/FIZZ1 signaling pathway is involved in the angiogenesis,and the mechanism may be related to the changes of intracellular Ca 2+concentration and then to regu-late the intracellular CaM and MLCK expression.