Investigation of a Drug with Potential Fast-Onset Efficacy in Affective Disorders: Pharmacological MRI of the 5-HT2A Receptor Agonist Psilocyn in the Rat.

Aisling Spain¹, Alexandre Khrapitchev¹, Trevor Sharp², Nicola R. Sibson¹, Chris Martin¹

Existing pharmacological treatments for affective disorders suffer from a lack of acute efficacy. Hallucinogenic drugs are potentially useful as treatments for depression and anxiety disorders, however further investigation of their physiological effects is necessary. To understand the acute effects of hallucinogen administration in vivo, 4 male Sprague-Dawley rats were administered the serotonin 2A receptor agonist, psilocyn and underwent BOLD imaging. Increases in BOLD signal were observed in prefrontal and subcortical areas, in structures implicated in the pathophysiology of mood disorders. These results illustrate the utility of fMRI in screening drugs for acute efficacy in mood disorders.