Repeated lysergic acid diethylamide (LSD) reverses stress-induced anxiety-like behavior, cortical synaptogenesis deficits and serotonergic neurotransmission decline
Neuropsychopharmacology March 17, 2022 Danilo de Gregorio, Antonio Inserra, Justine P. Enns et al. 89 citations
Lysergic acid diethylamide (LSD) is a serotonergic psychedelic being studied for potential anxiety and depression treatments, but its brain mechanisms are unclear. In male mice exposed to chronic restraint stress, acute LSD at doses of 5, 15, 30, and 60 μg/kg did not reduce anxiety or depression in non-stressed mice. However, daily 30 µg/kg LSD for 7 days prevented stress-induced anxiety-like behavior and the stress-induced loss of cortical dendritic spines. Repeated LSD increased the baseline firing rate of serotonin neurons in the dorsal raphe nucleus, which had been lowered by stress, and reduced the neurons' inhibitory response to a 5-HT1A receptor agonist. These effects suggest that repeated LSD prevents stress-induced anxiety by enhancing serotonin transmission and cortical spine density, possibly through desensitization of 5-HT1A receptors.