Interactions between the neuropeptide Y system and the hypothalamic-pituitary-adrenal axis.

The aim of this paper is to review the present knowledge of interactions between the neuropeptide Y (NPY) system and the hypothalamic-pituitary-adrenal (HPA) axis. On the basis of in vitro and in vivo studies of various animal species, we review the effects of NPY on all levels of HPA axis activity. We also describe the effects of glucocorticosteroids on the NPY system in the hypothalamus, including interactions between glucocorticosteroids and insulin. On the basis of available literature, we discuss the role of these interactions in the control of food intake and in the pathogenesis of obesity.