Caveolae Involved In Rat Vascular Smooth Muscle Cells Proliferation Induced By Apelin-13

Objective:1. TO observe the effects of caveolae on cell proliferation induced byapelin-13in ratVSMCs;2. To determine whether caveolin-1protein binds to signal molecules PI3K、ERK1/2.Methods:1. VSMCs were prepared from male Sprague-Dawley rats’ thoracic aortas by theprimary-explant method.2. The effect of β-cyclodextrin on cell proliferation induced by apelin-13weremeasured by MTT assay.3. VSMCs were incubated with apelin-13and β-cyclodextrin expression ofcaveolin-1were detected by Western Blotting.4. Formation of high molecular weight polyprotein component including caveolin-1and PI3K/ERK1/2was detected by immunoprecipitation.Results:1. MTT assay showed: The β-cyclodextrin(β-CD,5mmol/L,25h) enhanced VSMCsproliferation induced by apelin-13(P﹤0.05);2. WB showed: Treatment the VSMCs with apelin-13（0，6，8，12，24，48h）down-regulated the expression of caveolin-1by apelin-13and the effect wasdistinct at6hour(P﹤0.05);Treatment the VSMCs with apelin-13（0，1，2，4，8μM）down-regulated theexpression of caveolin-1by apelin-13and the effect was distinct at1μM(P﹤ 0.05);Pretreatment of the cell with β-CD (which was used to injury of caveolae),as thereported as previous, β-CD(5mmol/L) could enhanced down-regulated theexpression of caveolin-1induced by apelin-13(P﹤0.05);3. Co-IP analysis showed: apelin-13may cause dissociation of PI3K (ERK1/2) withcaveolin-1in VSMCs compared with control group;Conclusion: Caveolae involved in rat vascular smooth muscle cellsproliferation induced by apelin-13.