Glutamate Receptors Flashcards
What are the ionotropic glutamate receptors?
NMDA, AMPA and Kainate
What ions are NMDA receptors permeable to?
Sodium, Potassium, Calcium
How many subunits does the NMDA receptor have?
4
What is the subunit composition of an NMDA receptor?
Made up of any from GluN1-3
Always at least two GluN1 subunits
Usually GluN2A and GluN2B subunits
Ligands of the NMDA receptor
NMDA, Aspartate, Glutamate
Modulators of the NMDA receptor
Glycine, D-serine, Polyamines (such as magnesium and zinc)
Where can NMDA receptors be located?
Presynaptically
Postsynaptically
On glial cells
What are the functions of the NMDA receptor?
Slower, longer-lasting EPSPs
Synaptic plasticity - LTP and LTD
Excitotoxicity
What ions are AMPA receptors permeable to?
Sodium and potassium
How many subunits does the AMPA receptor have?
4
What are the 3 requirements for NMDA receptor activation?
Glutamate/Aspartate/NMDA binding
Co activation by glycine or D-serine
Depolarisation of neuron to remove the magnesium block
Where can AMPA receptors be located?
Postsynaptically
On glial cells
What are the functions of the AMPA receptor?
Fast EPSPs
What ions are Kainate receptors permeable to?
Sodium and potassium
How many subunits does the Kainate receptor have?
4
What is the subunit composition of an AMPA receptor?
Made of up any from GluA1-4 subunits
Always has GluA2 subunit
What is the subunit composition of a Kainate receptor?
Made up of any from GluK1-5 subunits
Where can Kainate receptors be located?
Presynaptically
Postsynaptically
(Limited distribution)
What are the functions of the Kainate receptor?
Fast EPSPs
Presynaptic inhibition
What are the metabotropic glutamate receptors?
mGlu1-8
What are the groups of metabotropic glutamate receptors and which receptors does each group contain?
Group 1: mGlu 1, 5
Group 2: mGlu 2, 3
Group 3: mGlu 4, 6-8
What G-protein are Group 1 mGlu receptors coupled to?
Gq
Where are Group 1 mGlu receptors located?
Postsyanptically
On glial cells
Where are Group 2 mGlu receptors located?
Presynaptically
Where are Group 3 mGlu receptors located?
Presynaptically
What G-protein are Group 2 and Group 3 mGlu receptors coupled to?
Gi/o
What is the function of Group 1 mGlu receptors?
Slow excitatory neurotransmission
Increases postsynaptic intracellular calcium
What is the function of Group 2 and Group 3 mGlu receptors?
Slow inhibitory neurotransmission
Open presynaptic potassium channels
Reduce presynaptic intracellular calcium
Prevent neurotransmitter release
