降钙素基因相关肽对大鼠血管平滑肌细胞CDK2和Cyclin E的影响

Effect of CGRP on the CDK2 and Cyclin E of rat vascular smooth muscle cell

目的:研究降钙素基因相关肽(CGRP)对大鼠血管平滑肌细胞中细胞周期蛋白依赖性激酶2(cyclin-dependent kinase 2,CDK2)和细胞周期蛋白E(Cyclin E)的影响,为阐明CGRP抑制血管平滑肌细胞增殖的细胞周期机制提供实验依据。方法:培养大鼠胸主动脉血管平滑肌细胞,分别用CGRP或/和10%FBS处理细胞。噻唑蓝比色法(MTT)观察CGRP对10%FBS诱导大鼠血管平滑肌细胞增殖的影响;流式细胞术分析细胞周期;Western blot检测CDK2和Cyclin E的表达。结果:CGRP能抑制10%FBS诱导的血管平滑肌细胞增殖,升高G0/G1期细胞百分比,降低S+G2+M期细胞百分比,抑制细胞内CDK2和Cyclin E表达。结论:CGRP能通过阻滞细胞周期由G0/G1期进入S期而抑制血管平滑肌细胞增殖,其作用机制可能与降低CDK2和Cyclin E表达有关。

AIM： To study the effect of calci- tonin gene-related peptide （CGRP） on cyclin-de- pendent kinase 2（CDK2） and Cyclin E of vascu- lar smooth muscle cell （VSMC）, and to elute the mechanism of inhibitory effect of CGRP on proliferation of VSMC in cell cycles. METH- ODS： VSMC were prepared from thoracic aortas of male Sprague-Dawley rat by explanting meth- od. The cell viability and cell cycle were deter- mined by MTT and Flow Cytometry, respective- ly. Western Blot was used to observe expres- sions of CDK2 and Cyclin E of VSMC. RE- SULTS： Pretreatment of VSMC with CGRP nificantly inhibited cells viability, decreased slg- theproportion of S phase and increased ratio of G0/ G1 that were induced by 10% FBS, simultane-ously, CGRP down-regulated the expressions of CDK2 and Cyclin E when cultured cells with 10% FBS at 12, 24 and 48 hours. CONCLU-SION= CGRP could inhibit the cell cycle of VSMC G0/G1 phase to S phase transition, by which the mechanism maybe involved in the de-crease expressions of CDK2 and Cyclin E.