What is the Difference Between AMPA and NMDA Receptors?
🆚 Go to Comparative Table 🆚AMPA and NMDA receptors are both glutamate receptors involved in neuronal communication, but they have distinct roles and characteristics. Here are the main differences between them:
- Ion permeability: Both AMPA and NMDA receptors are cation permeable, meaning they allow the passage of positively charged ions. However, AMPA receptors may or may not be calcium permeable, depending on the subunits that make up the receptor. In contrast, NMDA receptors are always calcium permeable.
- Activation: AMPA receptors can be activated by the chemical α-amino-3-hydroxy-5-methyl-4-isoxazole-propionate (AMPA), while NMDA receptors can be activated by N-methyl-D-aspartate (NMDA).
- Excitatory effects: Both receptors contribute to the excitation of neurons, but they have different effects on direction-selective and spatial phase-selective responses in the visual cortex. AMPA receptors are sufficient for generating direction selectivity, while NMDA receptors are responsible for highly direction-selective responses.
- Presence in synapses: While some glutamatergic synapses have only AMPA or only NMDA receptors, most have both AMPA and NMDA receptors.
- Disease association: Dysregulation of AMPA and NMDA receptors is known to lead to a variety of psychiatric conditions, such as schizophrenia.
In summary, AMPA and NMDA receptors are both glutamate receptors involved in excitatory neurotransmission, but they differ in their ion permeability, activation, and effects on neuronal responses. Most synapses contain both types of receptors, and dysfunction of these receptors can lead to various psychiatric disorders.
Comparative Table: AMPA vs NMDA Receptors
Here is a table comparing the differences between AMPA and NMDA receptors:
Feature | AMPA Receptors | NMDA Receptors |
---|---|---|
Type of agonist | α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA) | N-methyl-D-aspartate (NMDA) |
Subunits | Made up of four subunits per channel | Made up of two varieties of subunits: GluN1 and GluN2 |
Calcium permeability | May or may not be calcium permeable, depending on the subunits that make up the receptor | Calcium permeable |
Sodium and potassium influx | Increases in AMPA receptors | Increases along with calcium in NMDA receptors |
Magnesium ion block | AMPA receptors do not have a magnesium ion block | NMDA receptors have a magnesium ion block |
Activation | AMPA receptors are only activated by glutamate | NMDA receptors are activated by different agonists |
Co-stimulation | AMPA receptor does not need any co-stimulation for its activation | NMDA receptor requires co-stimulation of the receptor with glycine or serine |
Both AMPA and NMDA receptors are glutamate receptors that play different roles in neuronal communication in the central nervous system. They are non-selective, ligand-gated ion channels that mainly enable the passage of sodium and potassium ions.
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- Muscarinic vs Nicotinic Receptors
- Neuropeptides vs Neurotransmitters
- EPSP vs IPSP
- Excitatory vs Inhibitory Neurotransmitters
- Cyclic AMP vs AMP
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- Adrenergic vs Cholinergic Receptors
- Alpha vs Beta Receptors
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- Glutamine vs Glutamate
- Depolarization vs Repolarization
- Toll-Like Receptors vs Nod-Like Receptors
- D1 vs D2 Receptors
- Depolarization vs Hyperpolarization
- NeuN vs MAP2
- cAMP vs cGMP
- Action Potential vs Synaptic Potential