Explore the system
The NMDA coincidence gate
Combine transmitter binding and membrane depolarization to explore calcium entry and plasticity.
Sources and model limits
Original schematic. Positions show relationships; structures and concentrations are not to scale.
- Julien's Primer of Drug Action · 15 · 2 · The NMDA coincidence gate · PDF 30 · 2.17
- Professor deck 3 · NMDA activation conditions · PDF 32, 33, 34, 35
Course notes and existing practice
Learning objective
Compare glutamate and GABA receptor mechanisms and termination routes, including NMDA’s additional conditions.
Compare receptor families
The course introduces glutamate as a major excitatory transmitter and GABA as a major inhibitory transmitter. Glutamate examples include ionotropic AMPA, kainate, and NMDA, plus metabotropic mGlu receptors. GABA-A is ionotropic and GABA-B is metabotropic. The course’s broad excitatory/inhibitory descriptions are introductory framing, not universal rules independent of receptors and cell conditions.
NMDA requires more than glutamate
The NMDA slide combines glutamate binding with sufficient depolarization to relieve magnesium block and a co-agonist labeled glycine or D-serine in its figure. Therefore a simulation that opens NMDA solely when glutamate binds would omit required conditions at the supplied level. The next slide relates coincident activity to synaptic plasticity and longer-term changes involving AMPA.
Glial routes and recycling
The glutamate material shows transport into glia and a glutamine cycle, with EAAT named for uptake. The GABA material connects synthesis from glutamate to GAD, uptake to GAT, and metabolism to GABA-transaminase (GABA-T). Glial handling is part of both illustrations. These routes are not identical to the DAT/NET/SERT examples, even though all illustrate separate transport and metabolic steps.
- Glutamate
- The major excitatory amino-acid transmitter in the course’s introductory framing.
- GABA
- Gamma-aminobutyric acid, the major inhibitory transmitter in the introductory course framing.
- NMDA receptor
- An ionotropic glutamate receptor whose supplied activation model also requires relief of magnesium block and a co-agonist.
- GABA-A receptor
- The ionotropic GABA receptor class discussed in the deck.
- GABA-B receptor
- The metabotropic GABA receptor class discussed in the deck.
- EAAT
- Excitatory amino acid transporter, named in the glutamate uptake material.
- GAT
- GABA transporter, named in the GABA uptake material.
Professor deck 3, PDF pages 32, 33, 34, 35, 36, 38, 39. Explanation and terminology are paraphrased course material. Examples and study prompts are original, unscored teaching aids. Source conformance is separate from scientific or clinical review.
Worked examples are original instructional illustrations; they are not professor quotations or exam requirements.