The Inhibiting Effects of Losartan on Proliferation of Cultured Arterial Smooth Muscle Cell and Its Relationship with Neuropeptide Y

Objective To explore the mechanism of action of Losartan on vascular remodelling in hypertension and its relationship with neuroendocrine factor and renin-angiotensin system. Methods The study consisted of control group and other three treatment groups: Losartan group、NPY group、and Losartan+NPY group. More than 200 cells were scanned in each group. The methods of cellular culture, biochemistry and quantitative immunocytochemistry through ACAS570 were applied to investigate the proliferation of vascular smooth muscle cell (VSMC) and the expression of proliferating cell nuclear antigen (PCNA) in cultured rat VSMC treated with Losartan and Neuropeptide Y (NPY) stimulation. Results VSMC proliferation (by absorbauce) in the control group and other three examed groups: Losartan group、NPY group and Losartan+NPY group were 0.223 9±0.001 0、0.204 5±0.001 3、0.262 6±0.002 5、0.244 0±0.001 3, and PCNA (by fluorescence intensity) were 1 543±200、1 339±233、1 649±233、1 545±256. It was observed that losartan could inhibit the VSMC proliferation in vitro culture with and without NPY simulation. Compared with the control groups, the VSMC proliferation activity and expression of PCNA were obviously descreased in the losartan treated groups. Conclusion The results demonstrate that losartan has the inhibitive effects on VSMC profiferation and PCNA expression. The results also suggest that losartan has anti-NPY effect on VSMC in vascular remodelling of hypertensive vessels.