Mapping brain neuroleptic receptors in the live baboon.

An experimental strategy for external detection of specific neuroleptic receptors in living brain using positron emission transaxial tomography (PETT) and [11C]spiroperidol was applied to the mapping of brain neuroleptic receptors in the live baboon. A double injection of [11C]spiroperidol with an intervening time interval for carbon-11 decay and an intervening dose of (+)-butaclamol to block specific neuroleptic receptors produced two sets of PETT scans which were subtracted to produce a three-dimensional map of relative regional binding of neuroleptic receptors in the baboon brain. Sixty-five percent of the total radioactivity in the striatum was bound to neuroleptic receptors at 65 min after injection.