Demonstration of a neuropeptide Y (NPY)-like immunoreactivity in the pigeon retina

The distribution of neuropeptide Y (NPY)-like immunoreactivity in the pigeon retina was investigated by fluorescence immunohistochemistry. NPY-positive cells were found in central and peripheral retina. NPY somata were located in the proximal portion of the inner nuclear layer and their processes directed to the inner plexiform layer where they ramified in 3 immunoreactive bands. NPY might play a role as a neurotransmitter or neuromodulator in the pigeon retina.