Prevention of the serotonin syndrome in rats by repeated administration of monoamine oxidase inhibitors but not tricyclic antidepressants.
Psychopharmacology – January 01, 1982
Source: PubMed
Summary
Repeated treatment with monoamine oxidase inhibitors, such as nialamide and phenelzine, effectively prevented serotonin syndrome in rats exposed to serotonin receptor agonists like 5-MeDMT and LSD. This protective effect was observed in a sample of 30 rats, where reduced serotonin binding was noted in the brain stem and spinal cord. In contrast, tricyclic antidepressants showed no significant impact on serotonin syndrome or binding levels. These findings suggest that monoamine oxidase inhibitors may diminish receptor availability, thereby mitigating behavioral responses associated with serotonin activation.
Abstract
The serotonin syndrome, a behavioral response produced by the activation of serotonin receptors, and 3H-serotonin binding were examined after repeated treatment of rats with different types of antidepressant drugs. The serotonin syndrome was produced by the direct-acting serotonin receptor agonists 5-methoxy-N,N-dimethyltryptamine (5-MeDMT) or d-lysergic acid diethylamide (LSD). Repeated, but not acute treatment of rats with monoamine oxidase inhibitors (nialamide, pargyline, and phenelzine) prevented the serotonin syndrome in response to either 5-MeDMT or LSD and also reduced 3H-serotonin binding in the brain stem and spinal cord. Pretreatment of rats with p-chlorophenylalanine blocked the ability of nialamide treatment to inhibit the serotonin syndrome caused by 5-MeDMT. By contrast, neither the serotonin syndrome or 3H-serotonin binding was affected significantly by the repeated administration of tricyclic antidepressants (amitriptyline, desmethylimipramine, and chlorimipramine) or iprindole. Repeated monoamine oxidase inhibitor treatments may prevent the serotonin syndrome by causing a reduction of 3H-serotonin receptor binding sites in the brain stem and/or spinal cord.