Central bombesin inhibits food intake and the orexigenic effect of neuropeptide Y in the neonatal chick

It is well known that central injection of bombesin (BN) suppresses feeding in mammalian and avian species, but the anorexigenic effect of central BN are still open with special reference to the chick. The dose response (0, 0 .1 and 0.5 mug) of intracerebroventricular (ICV) injection of BN was examin ed in Experiment 1. ICV injection of BN inhibited food intake in a dose-dep endent manner. Experiment 2 was done to determine whether BN interacts with the orexigenic effect of neuropeptide Y (NPY) in the neonatal chick. Centr al administration of NPY (2.5 mug) greatly enhanced food intake, but co-inj ection of BN (0.5 mug) suppressed food intake. The dose response of NPY (2. 5 mug) co-injected with three levels of BN (0, 0.1 and 0.5 Gig) was examine d in Experiment 3. ICV injection of BN attenuated the hyperphagia by NPY in a dose-related fashion. It is suggested that central BN may interact with NPY for the regulation of feeding in the neonatal chick. (C) 2000 Elsevier Science Inc. All rights reserved.