Human Cortical Serotonin 2A Receptor Occupancy by Psilocybin Measured Using [¹¹C]MDL 100,907 Dynamic PET and a Resting-State fMRI-Based Brain Parcellation.

Abstract

Psilocybin (a serotonin 2A, or 5-HT_2A, receptor agonist) has shown preliminary efficacy as a treatment for mood and substance use disorders. The current report utilized positron emission tomography (PET) with the selective 5-HT_2A receptor inverse agonist radioligand [¹¹C]MDL 100,907 (a.k.a. M100,907) and cortical regions of interest (ROIs) derived from resting-state functional connectivity-based brain parcellations in 4 healthy volunteers (2 females) to determine regional occupancy/target engagement of 5-HT_2A receptors after oral administration of a psychoactive dose of psilocybin (10 mg/70 kg). Average 5-HT_2A receptor occupancy across all ROIs was 39.5% (± 10.9% SD). Three of the ROIs with greatest occupancy (between 63.12 and 74.72% occupancy) were within the default mode network (subgenual anterior cingulate and bilateral angular gyri). However, marked individual variability in regional occupancy was observed across individuals. These data support further investigation of the relationship between individual differences in the acute and enduring effects of psilocybin and the degree of regional 5-HT_2A receptor occupancy.

Topics & conditions

Detected automatically by Psychedelic Commons from the title and abstract, not labels from the source. They may be incomplete.

Keywords