User:Amyngu/Site-specific functions of Central Neuropeptide Y

The neuropeptide Y (NPY) family and their Y-receptors are heavily involved in the regulation of energy homeostasis. The NPY family consists of three 36-amino acid peptides: NPY, peptide YY and pancreatic polypeptide. These influence energy homeostasis via their interactions with five G-protein-coupled Y receptors: Y1, Y2, Y4, Y5 and y6 (mouse).

Directional Research Shift
Classically, the NPY system and its Y-receptors have been studied in the arcuate nucleus and the paraventricular nucleus of the hypothalamus. However, in recent times, emphasis has shifted towards other nuclei of the hypothalamus, through use of conditional Y-receptor knockout models. This new shift has aided in the discoveries that NPY overexpression in the dorsomedial hypothalamus increases food intake whereas its ablation in this area reduces hyperphagia and obesity. Similarly, NPY exerts functions orexigenically in the ventromedial nucleus. However, specific arcuate Y2-receptor deletion results in positive energy balance, suggesting the NPY family demonstrates location-specific functions.

Importance
It is becoming clearer that the functions of the NPY family and its Y-receptors are dependant on their location in the CNS. Current developments of conditional Y-receptor knockout and site-specific transgene models are being used to elucidate these functions, thus showing the importance of these new technologies.