NPY and NPY receptors in vascular remodeling.

Neuropeptide Y (NPY) is a sympathetic neurotransmitter that acts on multiple receptors (Y1-Y6) and exerts a variety of cardiovascular effects. Originally known as a vasoconstrictor acting on Y1 receptors, NPY is also a potent angiogenic factor as well as a powerful stimulator of vascular smooth muscle proliferation and atherogenesis in vitro and in vivo. These two types of vascular remodeling are predominantly mediated by Y2/Y5 and Y1 receptors respectively, but evidence suggests that all receptors are activated in both conditions. A strategy to inhibit neointima formation and atherosclerotic lesions without impairing ischemic angiogenesis and collateral vessel formation has been a major challenge to overcome. Studies in rodents show that Y1 receptor antagonist inhibits angioplasty-induced atherosclerotic-like vascular remodeling, without affecting ischemic revascularization. Conversely, Y2 receptor activation appears to be sufficient to stimulate angiogenesis in various animal models. Thus, the use of selective receptor agonists to promote angiogenesis through the Y2 receptor while antagonizing the pro-atherosclerotic and pro-stenotic effects with Y1 receptor-selective antagonists may help to successfully treat vascular remodeling in cardiovascular diseases.