Purpose: Like other psychedelics, D-lysergic acid diethylamide (LSD) affects numerous serotonin receptors, and according to the current dogma, the 5-HT 2A receptors are considered the main target for its hallucinogenic effects. LSD, however, also displays agonistic activity at the 5-HT 5A receptors, which mediate some of LSD-induced behavioural effects. Methods: Using male Sprague Dawley rats,...