A nitric oxide synthase inhibitor attenuates neuropeptide y - and clonidine- induced feeding in the neonatal chick

It is reported that inhibition of nitric oxide (NO) synthase (NOS) decreased food intake in mammalian and avian species. On the other liand, central administration of α₃-agonists stimulated. food intake in both species. Similarly, neuropeptide Y (NPY) has the orexigenic effect mediated by α₂, receptors. The present study was done to determine whether central injection of N^G-nitro-L-arginine methyl ester (L-NAME), a NOS inhibitor, in the neonatal chick modulates uie increase in food intake induced by NPY- and clonidine (CLON, a. specifie α₂-agonist)- induced food intake. Both NPY (2.5 μg)- and CLON (50 ng)-induced food. intake of neona.tal chicks was significantly attenuated by co- administration with the higher doses of L-NAME (0, 0.2, 0.4 and 0.8 mg). Our results suggest that NO may internet with orexigenie systems in modulating food intake in the neonatal chick.