The Effect of Antipsychotics on the High-Affinity State of D2 and D3 Receptors

Abstract

Antipsychotics block both the high- and low-affinity states of the D(2) receptors across the brain, but antipsychotic treatment does not block the [(11)C]-(+)-PHNO signal in the D(3) receptor-rich regions, despite the ongoing D(2) receptor blockade. This [(11)C]-(+)-PHNO signal in regions such as the globus pallidus seems increased despite antipsychotic treatment and is displaceable by a D(3) receptor-preferring agonist. The radiotracer [(11)C]-(+)-PHNO and the data open up new avenues for exploring the potential therapeutic significance of the D(3) receptor in schizophrenia.