In vivo interaction of neuropeptide Y and peptide YY with sigma receptor sites in the mouse brain.

Neuropeptide Y (NPY-(1-36)), peptide YY (PYY) and various other peptides were investigated for their interaction with the binding of [3H](+)-SKF10,047 to sigma binding sites in mouse hippocampus in vivo. NPY-(1-36), PYY-(1-36), [Leu31,Pro34]NPY, NPY-(2-36), and NPY-(3-36) inhibited the labelling of a population of haloperidol-sensitive binding sites corresponding to 35% of the specific binding. These in vivo binding results confirm the previous interaction already reported between NPY peptides and sigma binding sites.