Emerging functions for neuropeptide Y5 receptors

The Y-5 subtype of neuropeptide Y(NPY) receptors has raised considerable interest as a mediator of NPY-stimulated food intake, but with the advent of recent data, this hypothesis has come into question. Moreover, Y-5 receptor-selective drugs might not be specific for food intake because additional functions in the central and peripheral nervous systems, including endogenous anti-epileptic activity, attenuation of morphine withdrawal symptoms, enhancement of diuresis and natriuresis, lowering of blood glucose and reduction of acetylcholine release in the ileum, have recently been reported to occur via Y-5-like receptors. Given that mRNA for the cloned Y-5 receptor is apparently restricted to the CNS, Angela Bischoff and Martin Michel discuss the possible existence of additional NPY receptor subtypes with Y-5-like recognition features and their presence in peripheral tissues.