Effects of cyclosporin A on neuropeptide Y-induced proliferation of cultured vascular smooth muscle cells

To sutdy the role of caldicneurin (CaN)-dependent signaling pathway in proliferation of vascular smooth muscle cells (VSMCs) by observing the effects of cyclosporin A (CsA) on proliferation of neuropeptide Y(NPY)-induced rat VSMCs. Upon the model of cultured rat VSMCs, the study consisted of three groups: NPY group, CsA+NPY group and control group. CaN activity was determinated by enzyme reaction phosphone measurement. The methods of biochemistry (MTT) and quantitative immunocytochemistry were applied to investigate the proliferation of VSMC and the expression of proliferation cell nuclear antigen (PCNA) in cultured rat VSMCs. Compared with the control group, the VSMC^s CaN activity, proliferation activity and expression of PCNA (by phto densitometry A_(PCNA)) were obvously increased in NPY group (P<0.01 or P<0.05). Meanwhile, CsA markedly inhibited CaN activity, prliferation activity and the expression of PCNA with a signifcantl y difference from NPY group (P<0.01 or P<0.050. The study indicates that CsA has a signifcanlty difference from NPY group (P<0.01 or P<0.05). The study indicates that CsA has a signifcantl inhibitory efect on proliferation of VSMC stimulated by NPY, which may be related to blocking CaN-medicated signal transduction.