Effects of Angiotensin Ⅱ Type 2 Receptor on the Proliferation and M igration of Rat Vascular Smooth Muscle Cells in vitro / 中华高血压杂志

ABSTRACT

Objective To study the proliferation and migration of vascular smooth muscle cell (VSMC) after transferred angiotensin Ⅱ (AngⅡ) type 2 receptor (AT2R) gene. 　Methods The recombinant adenoviral vector, AdCMV-AT2R, containing rat AT2 receptor gene was constructed by homologous recombination, and transfered to rat VSMC in vitro. The expression of AT2R mR NA was detected by RT-PCR. The rate of expression and the change of cell cycle in VSMC were analysed by flow cytometry. These assays including cell devision index. Incorporation of bromodeoxyuridine(BrdU) and 3-(4,5-dimethyl-thiazol-2-yl)2,5-diphenyltetrazolium bromide( MTT) were used to determine the proliferation of VSMC. The modified Boyden's chamber method was used to test the migration of VSMC. The r e-organization of F-actin in VSMC was analysed by confocal microscopy. 　Results RT-PCR showed that the expression of AT2R mRNA increased substantially in transferred VSMC, and the peak value of expression rate is about 89.51% at 48 hours. When the expression of AT2R is at peak value, the ratio of S, G2 and M periods was reduced from 31.7% to 13.9%(P<0.05). The OD values of MTT and BrdU incorporation were reduced by 61.4% and 51.6% respectively(P<0.0(1). the number of VSMC migration was reduced by 62.2%(P<0.05) and the expression of F-actin was also decreased signific antly. 　Conclusion AdCMV-AT2R induced high level expression of AT2 receptor in cultured rat VSMC and its expression can significantly inhibit the proliferation and migration of rats VSMC in vitro.