Opiate receptor distribution in the cerebral cortex of the Rhesus monkey

The distribution of opiate receptors in the cerebral cortex of the rhesus monkey (Macaca mulatta) was determined by autoradiographic visualization of [3H]naloxone binding to tissue sections. Naloxone was bound in relatively large amounts to the cortical laminae containing the cell bodies of output neurons, to a varying set of additional laminae in different cortical fields, to fields closer to more primitive types of cortex, and to polysensory cortical fields. From these laminar and areal variations in distribution, it appears that opiate receptors play a role in specific aspects of cortical function.