... Y5 and y6) thatvary in their binding profiles and in their distributionin the central nervous system and periphery. Y1, Y2 and Y5 are the best characterized NPY receptors, and the majority of ... stromal cells and osteoblasts [40,46–48],despite the absence of the other Y receptors (Y2, Y4,Y5 and y6) [40,46]. In addition to the presence of NPY-immunoreactive fibers and the presence of NPY receptors, ... central control of bone formation by hypotha-lamic Y2, if the existence of Y2 in osteoblasts is fur-ther demonstrated, the complexity of the regulation of bone homeostasis by the NPY system...