Unlike conventional antidepressants which are used to elevate concentrations of the neurotransmitters serotonin, dopamine, or noradrenaline ketamine influences the glutamate system. Glutamate, the major excitatory neurotransmitter, plays a central role in mediating nearly all forms of brain function, including learning, memory, cognition, and emotion.

Nonetheless, research on ketamine s chemistry might help to identify mechanisms for addressing treatment resistant depression that are based on glutamate driven neuroplasticity. Indeed, pharmaceutical companies have already begun to investigate other NMDA receptor antagonists, together with drugs that act on a different part of the glutamate system, as possible treatments for depression.