[$^{3}$H]Lysergic Acid Diethylamide: Cellular Autoradiographic Localization in Rat Brain

Intravenous administration of [$^{3}$H]lysergic acid diethylamide (LSD) to rats resulted in accumulation of the drug in the brain within 15 minutes. Auto-radiographic methods were used to differentiate free and bound [$^{3}$H]LSD in brain tissue. Free [$^{3}$H]LSD was generally distributed in the pituitary and pineal glands, cerebellum, hippocampus, and choroid plexus. Bound [$^{3}$H]LSD was localized in neurons of the cortex, caudate nucleus, midbrain, and medulla, as well as in choroid plexus epithelium.