Citalopram antagonizes the stimulation by lysergic acid diethylamide of presynaptic inhibitory serotonin autoreceptors in the rat hypothalamus.
Journal of Pharmacology and Experimental Therapeutics July 1, 1982 Salomón Z. Langer, Chantal Moret 100 citations
In slices of rat hypothalamus, the release of the neurotransmitter serotonin (5-HT) depends on the mechanism that triggers it. Electrically stimulated release requires calcium and is modulated by drugs that affect serotonin autoreceptors—methiothepin increases it, while LSD decreases it. In contrast, fenfluramine-induced release is calcium-independent and unaffected by these drugs. Citalopram, a serotonin reuptake inhibitor, blocks LSD's inhibitory effect on electrically evoked release without altering baseline release. The findings suggest that presynaptic serotonin autoreceptors regulate release only when release depends on calcium, and that LSD's strong presynaptic inhibition of serotonin transmission may contribute to its central effects. The interaction between citalopram and LSD does not appear to involve competition at the same receptor.