Effect Of CGRP On The Proliferation Of Vascular Smooth Cell And Expression Of CDK2 And Cyclin E

AIM To investigate the effect of calcitonin gene-related peptide(CGRP) on the proliferation of vascular smooth muscle cells induced by 10%FBS, and further explore whether this effect is related to the activity of ERK1/2 and the expression of CDK2 ,CyclinE.METHODS Vascular smooth muscle cells(VSMCs)were prepared from thoracic aortas of male Sprague-Dawley rat by the explant method. The passages of cells 3~10 were used for the present studies. The viability and cell cycle of cultured VSMCs were respectively estimated by MTT assay and Flow Cytometry (FCM).Western blot was used to observe the effects of pretreatment with CGRP on the expression of p-ERK1/2, CDK2, CyclinE induced by 10%FBS in VSMCs.RESULTS 10%FBS or Angâ…¡(100nM) time-dependently increased the viability of VSMCs. CGRP dose-dependently decreased the viability of VSMCs. Pretreatment of the cell with CGRP significantly inhibited VSMCs proliferation induced by 10%FBS. FCM analysis showed that CGRP decreased the proportion of S phase but increased G0/G1. Results also demonstrated that CGRP down-regulated the activation of p-ERK1/2, CDK2 and CyclinE induced by 10%FBS during 12~48 hour, which was partly attenuated by CGRP8-37, an antagonist of CGRP-1 receptors. CONCLUSION In the present study,we found that pretreatment with CGRP inhibited the proliferation of VSMCs induced by 10%FBS. The effects of CGRP maybe involved with the activity of ERK1/2 signal transduction pathway, down-regulated the expression of CDK2, CyclinE and inhibited cell cycle through G1 phase into S phase.