Abstract
Modern research data suggest a therapeutic role for serotonergic psychedelics in depression and other neuropsychiatric disorders, although psychotomimetic effects may limit their widespread utilization. Serotonergic psychedelics enhance neuroplasticity via serotonin 2 A receptors (5HT2AR) activation and complex serotonergic-glutamatergic interactions involving the ionotropic glutamate receptors, tropomyosin receptor kinase B (TrkB) and the mammalian target of rapamycin (mTOR). N-methyl-d-aspartate receptors (NMDAR) channel antagonists, i.e. ketamine, and glycine modulatory site full and partial agonists, i.e., D-serine (DSR) and D-cycloserine (DCS), share some of these mechanisms of action and have neuroplastic and antidepressant effects. Moreover, procognitive effects have been reported for DSR and DCS and 5HT2AR-NMDAR interactions modulate neuronal excitability in prefrontal cortex and represent a target for new antipsychotics. We hypothesize that the synchronous administration of a psychedelic and a NMDAR modulator may increase the therapeutic impact of each of the treatment components and allow for dose adjustments and improved safety. We propose to initially focus research on the acute concurrent administration of psilocybin and DSR or DCS in depression.