Imaging of striatal dopamine release elicited with NMDA antagonists: is there anything there to be seen?

Increased release of striatal dopamine, indexed with in vivo imaging of the D(2) receptor, has been reported following an acute challenge with N-methyl-D-aspartate (NMDA) antagonist ketamine in humans. Replications of this result have not been consistently successful. The aim of this manuscript is to evaluate in vivo imaging examination of NMDA antagonism on striataL dopamine release in published reports of humans and pre-clinical species. The literature is evaluated in conjunction with insights on the effect of NMDA antagonism on dopamine release, elicited from microdialysis and tissue turnover studies, and suggestions for future studies are made.