Interaction between LSD and dopamine D2/3 binding sites in pig brain
Synapse January 1, 2005 Luciano Minuzzi, George G. Nomikos, Mark Wade et al. 25 citations
LSD reduces the binding potential of a dopamine D2/3 receptor tracer in the striatum of pigs, suggesting a direct interaction with these receptors. In a PET study, the binding potential of [11C]raclopride decreased by 19% four hours after LSD administration, without changes in cerebral blood flow. In vitro experiments showed LSD displaces the tracer from pig brain tissue with an IC50 of 275 nM, and a two-site model indicated a subnanomolar component comprising 20% of binding. Microdialysis in rats found no changes in dopamine or its metabolites. These findings indicate LSD directly occupies a portion of dopamine D2/3 receptors, which may contribute to its psychoactive effects.