Glutamate Flashcards
Glutamate is synthesised from
Glutamine
Glutamate reuptake is done by
Excitatory amino acid transporters (EAAT)
MSG is a _____ ______ and stands for…
Food additive, monosodium glutamate
Cells which are ‘metabolic cleaner uppers’
Glial cells
Glutamine is converted into glutamate by
Glutaminase
Glutamate is converted into glutamine in glial cells by
Glutamine synthase
The three classes of ionotropic glutamate receptors are
NMDA, AMPA, KA
The three classes of metabotropic glutamate receptors are
Group 1, group 2, group 3
How many subunits do ionotropic glutamate receptors have?
4
How many segments does each of the 4 subunits have in a ionotropic glutamate receptor?
4 segments
Which subunit segment does not span the membrane?
Segment 2
Which receptor doesn’t exist, homomeric AMPA, or homomeric NMDA?
Homomeric NMDA
Which subunit is needed for a functional NMDA receptor?
GluN1
What are the agonists for AMPA other than AMPA and glutamate?
KA
What are the agonists for NMDA other than NMDA and glutamate?
aspartate
What is a competitive antagonist of AMPA?
NBQX
What are the antagonists of NMDA?
Ketamine, CPP (competitive), PCP
What are the co-agonists of NMDA?
Glycine/serine
What ions do AMPA and NMDA control the passage of?
Na+ in, K+ out, NMDA controls Ca2+ in
Which ionotropic glutamate receptor is both ligand and voltage gated?
NMDA
What blocks the NMDA channel until depolarisation?
Mg2+
Which is involved in fast excitation, ionotropic or metabotropic (GPCR) glutamate receptors?
Ionotropic
Metabotropic receptors activate what?
Enzymes or ion channels
What ion controls neurotransmitter release?
Ca2+
Presynaptically, mGluR couple to which ion channel and what does this control?
Ca2+, neurotransmitter (glutamate) release
Postsynaptically, mGluR couple to which ion channel?
K+
How does mGluR control neurotransmitter release?
Glutamate binds to mGluR, G protein activates, beta gamma unit causes Ca2+ channel to close, reduced influx
How does mGluR control slow depolarisation postsynaptically?
Glutamate binds to mGluR, G protein activates, beta gamma unit causes K+ channel to close, reduced K+ efflux out of the cell
What effect does an active alpha unit have in the postsynapse?
Regulating Ca2+ release and postsynaptic excitability (Second messenger cascade by Gq coupled receptor)
The postsynaptic functions of mGluR are:
Produce slow depolarisation (K+) and control Ca2+ intracellular release
Which group of mGluR is postsynaptic?
Group 1 (mGluR1 and mGluR5)
Which groups of mGluR are presynaptic?
Group 2/3 (mGluR 2,3,4,7,8)
What are the glutamate transporters called?
VGlut
