antecedently used as a horse tranquilliser and party drug , ketaminehas reinvented itself over the preceding few years as a treatment for Great Depression . imposingly , the drug has been show toalleviate depressive symptoms in as picayune as 24 hours , which represents a major improvement on traditional medications like selective serotonin reuptake inhibitor ( SSRIs ) , which can take weeks or months to bring forth an event . concord to a new study in the journalMolecular Psychiatry , ketamine hydrochloride ’s ability to put up such rapid relief may hinge on its capacity to inhibit a picky neurotransmitter called glutamate .
" Elevated glutamate handout has been linked to emphasis , depression and other mood disorders , so lower glutamate spirit level may explain some of the effects of ketamine , " explained study source Per Svenningsson in astatement .
The approximation that ketamine may somehow regulate the effects of glutamate is not new , although scientists have skin to understand the influence that the drug exerts over this key neurotransmitter . former research has revealed that Ketalar blocks a character of brain sense organ known asNMDA glutamate receptors , thereby preventing brain cells from becoming overstimulated by glutamate . freestanding study , meanwhile , have signal that ketamine ’s speedy anti - depressant personal effects may be mediated by one of its metabolites called(2R,6R)-HNK , which truss to a different class of receptor know as AMPA receptor .
To empathize how these various mechanisms interact with one another , the source of the latest study injected mice with both ketamine and ( 2R,6R)-HNK . Doing so produced an quick decrease in glutamate floor in the gnawer ’ brains , and also led to a simplification in depressive symptoms such as an unwillingness to swim when place in water .
Further psychoanalysis revealed that both ketamine and ( 2R,6R)-HNK activate AMPA receptors on postsynaptic nerve cell , which usually encounter glutamate release by presynaptic neurons . This caused a neurotransmitter called adenosine to be secrete back across the synapse and bind to receptors on presynaptic neurons , preventing them from releasingglutamate .
Within 30 minutes , the researchers discover a significant decrease in glutamate secretions in the animals ’ brainiac . As a import , mice that had been genetically direct to sustain from depression displayed an immediate increase in their desire to swim , thus reassert Ketalar ’s rapid anti - depressive effect .
However , when the researcher chemically obturate postsynaptic AMPA receptors , glutamate level increased and mouse no longer demonstrated reductions in depression . This finding corroborates the notion that both ketamine and ( 2R,6R)-HNK trust on AMPA receptors for inhibit the release of glutamate and rarefy depressive symptoms .
Summing up the meaning of their piece of work , the study authors suggest that these finding could start the door for the development of new anti - depressants that work via the same mechanics but do not produce any of the trippy side - burden for which ketamine is famous .
