Ketamine works to relieve depression and anxiety symptoms by promoting neuroplasticity, the brain's ability to form new neural connections.
Unlike traditional antidepressants that primarily affect neurotransmitters like serotonin and can take weeks to show effects, ketamine acts on a different neurotransmitter, glutamate, which is the most abundant excitatory neurotransmitter in the brain.
Here's how ketamine helps relieve depression and anxiety:
Glutamate Activation: Ketamine blocks a receptor in the brain called the NMDA receptor, which is involved in glutamate transmission. By blocking these receptors, ketamine increases the levels of glutamate in the spaces between neurons.
Synapse Formation: The increased glutamate release activates a different set of receptors (AMPA receptors), leading to a cascade of events inside the neurons. This results in the release of brain-derived neurotrophic factor (BDNF), which promotes the growth and strengthening of synapses, or connections between neurons. This process enhances neuroplasticity, which is crucial for learning, memory, and adapting to new experiences.
Rapid Symptom Relief: The changes in synaptic connections can occur rapidly, leading to an almost immediate alleviation of depressive or anxious symptoms for some individuals, often within hours or days. This rapid action contrasts with conventional antidepressants, which may take several weeks to become effective.
Resetting Neural Circuits: By promoting neuroplasticity and helping to restore synaptic connections that have been damaged by chronic stress or depression, ketamine may "reset" brain circuits involved in mood regulation, providing relief from depression symptoms.