Effects of CaN Activity and c-fos Expression Level in the Proliferation of Rat VSMCs Stimulated by Neuropeptide Y

Objective To study the effects of calcineurin(CaN) activity and c-fos expression level in the proliferation of rat vascular smooth muscle cells(VSMCs) stimulated by neuropeptide Y. Methods Rat VSMCs were cultured in vitro using tissuepiece-anchorage primary culture. Rat VSMCs were treated with neuropeptide Y(NPY) to form cell proliferation model. Cyclosporin(CsA), a specific inhabitor of CaN, was used to block CaN-depended signal transduction pathway in rat VSMCs stimulated by NPY.The effect of different agent on CaN activity, proliferation activity and the expression level of c-fos were observed.Results Within a certain concentration coverage, NPY(10 -7 -10 -5 mol/L) increased CaN activity of VSMCs by a dose-dependent way to a different extent, meanwhile, increased the proliferation activity(A_ MTT value) of VSMCs with markedly statistics difference (P0.01 or P0.001) in comparison with the control. While the treating with CsA(1μmol/L) obviously decreased the proliferationactivity and the expression of c-fos in VSMCs of NPY+CsA group in comparison with NPY group(P0.001). Conclusion CaN take part in the proliferation of cultured rat vascular smooth muscle cells stimulated by neuropeptide Y, and activated the transcript and expression of immediate-early gene, and then promoted proliferation of cells.