Adenoviral-mediated transference of the rat angiotensin II type 2 receptor gene inhibits the proliferation of vascular smooth muscle cells in vitro

Objective To study the effect on the proliferation of vascular smooth muscle cells(VSMC) after transferring angiotensin Ⅱ(AngⅡ) type 2 receptor(AT2R) gene.Methods The recombinant adenoviral vector AdcCMV AT2R, containing rat AT2 receptor gene which was constracted by homologous recombination, was used to transfer AT2 receptor gene to rat VSMC in vitro. The expression of AT2R mRNA was detected by RT PCR. The rate of expression and the change of cell cycle in VSMC were analysed by flow cytometry. Cell devision index, incorporation of bromodeoxyuridine(BrdU)and 3 (4,5 dimethyl thiazol 2 yl)2,5 diphenytetrazolium bromide(MTT) were used to determine the proliferation of VSMC, respectively.Results RT PCR showed that the expression of AT2R mRNA increased obviously in transferred VSMC, and the peak value of expression rate was about 89.51% at 48 hours. When the expression of AT2R was at peak value, the ratio of S and G2 M periods was reduced from 31.7% to 13.9%(P0.05) and the index of cell division from 37.4% to 9.6%(P0.01). The OD values of MTT and BrdU incorporation were reduced by 61.4% and 51.6% respectively(P0.01).Conclusion Our study indicates that AdCMV AT2R can generate high level expression of AT2 receptor in cultured rat VSMC and its expression can significantly inhibit the proliferation of rats VSMC in vitro. It may be a new selection for the gene therapy of restenosis after angioplasty.