Regional distribution of muscarinic acetylcholine receptors in the telencephalon of the pigeon (Columbia livia f. domestica).

The distribution of muscarinic ACh receptors was studied autoradiographically in cryostat sections of the pigeon telencephalon using 3H-Quinuclidinylbenzylate (QNB) as a ligand. Highest receptor density was observed in the hyperstriatum ventrale, palaeostriatum augmentatum, septum, and parts of the archistriatum In sites of known sensory input of neostriatum (field L) and ectostriatum low receptor binding was observed. Acetylcholinesterase distribution is in good agreement with the receptor picture only in the basal telencephalon. In the pallium differences in the pattern of these two components can be seen.