p27和p21在血管平滑肌细胞增殖信号传导中的作用机制研究

目的　研究p2 7及p2 1在血管平滑肌细胞增殖中的作用。方法　分离SD大鼠主动脉中层平滑肌,培养平滑肌细胞。实验前无血清培养基培养4 8h ,使细胞进入静止期。以无血清组为对照组,培养基中分别加入血小板源性生长因子-BB(PDGF -BB) 2 0 μg/L和AngⅡ10 -6M ,分别在刺激6 ,12 ,2 4h收集细胞。采用Western蛋白印记法,检测平滑肌细胞内p2 7和p2 1蛋白表达量。结果　与AngⅡ组比较,PDGF -BB组p2 7蛋白表达量明显下降,刺激2 4hp2 7蛋白表达量下降幅度最大,较对照组降低5 9.32 % ;AngⅡ组p2 7光密度值与对照组相近,比较无显著性差异。PDGF -BB组p2 1蛋白表达量则升高,刺激2 4h时PDGF -BB组光密度值较对照组增加了6 6 .95 % ,较AngⅡ组增加了10 1.14 % ,PDGF -BB组与对照组和AngⅡ组比较均有显著性差异(P <0 .0 1) ;AngⅡ组较对照组减少17% ,2组比较无显著性差异。结论　p2 7蛋白表达量在血管平滑肌细胞增殖中降低,而p2 1蛋白表达量升高,两者在血管平滑肌细胞增殖中的作用不同。

Action mechanism study of p27 and p21 in proliferative signal transduction in vascular smooth muscle cell

Objective It is to study the action of p27 and p21 in proliferation in vascular smooth muscle cell. Methods The medial smooth muscle of SD rat arteriae aorta was separated and the smooth muscle cell was cultivated. The cell was cultivated in non-serum medium before experiment to make it turn to stationary phase. The non-serum group was as control group. Then PDGF-BB 20 μg/L and AngⅡ 10 -6 M were respectively added in medium. The cell was respectively collected after excited 6, 12, 24 h. The p27 and p21 proteinum expression quantities in the smooth muscle cell were detected with Western blot analysis. Results Compared with AngⅡ group, the p27 proteinum expression quantity in PDGF-BB group lowered obviously. The lower extent of the p27 proteinum expression quantity was maximal at excited 24 h and that lowered 59.32% compared with control group. The p27 optical density value in AngⅡ group was closed to that in control group and there was no significant difference. The p21 proteinum expression quantity in PDGF-BB group heightened. The optical density value in PDGF-BB group was increased 66.95% at excited 24 h compared with control group and increased 101.14% compared with AngⅡ group, and there were significant difference (P<0.01). The optical density value in AngⅡ group was decreased 17% compared control group and there was no significant difference. Conclusion The p27 proteinum expression quantity lowers in proliferation in vascular smooth muscle cell but the p21 proteinum expression quantity heightens. The actions of the both in proliferation in vascular smooth muscle cell are different.