NMDA Receptor Antagonism
Ketamine binds inside the NMDA receptor channel, preferentially when it's already open — a use-dependent block.
Key points
- Preferential targeting: ketamine binds GABAergic interneurons that express more open NMDA receptors at rest.
- Disinhibition: blocking those interneurons reduces their dampening effect on excitatory neurons.
- Net result: a paradoxical glutamate surge in cortical regions — the actual trigger for downstream effects.
Why this isn't the whole story
Other NMDA antagonists (memantine, lanicemine) don't reliably reproduce ketamine's antidepressant effects. This tells us NMDA antagonism is necessary but not sufficient — something about ketamine's specific kinetics, metabolites, and downstream cascade matters.
Educational use only. The content on this page is provided for general educational purposes and does not constitute medical advice, diagnosis, or treatment. Ketamine and related therapies carry risks and are appropriate only under qualified medical supervision. Always consult a licensed healthcare professional about your individual situation. Information may change as research evolves.