Excitatory Amino Acids Flashcards
What are the criteria for a neurotransmitter?
Made by neurons, released by postsynaptic neurons, must be active against postsynaptic receptors, must be inactivated, must have a physiological purpose.
What do umami taste buds in the tongue detect?
Glutamate.
By what mechanism is glutamate released?
Calcium-dependent exocytosis.
Which classes of glutamate receptors are ionotropic?
NMDA, AMPA, KA.
Which classes of glutamate receptors are metabotropic?
Groups 1,2, and 3. These are names with a lowercase “m” before the Glu name.
What are agonists for AMPA and KA receptors?
Glutamate, AMPA, KA.
What are antagonists for AMPA and KA receptors?
CNQX, NBQX.
What ions do AMPA and KA receptors pass upon activation? How does this differ from younger people?
Sodium and potassium ions. Calcium ions are also passed if there is no GluR2 and these receptors become less prevalent as one ages.
What type of response do AMPA and KA receptors illicit?
Fast voltage sensitive response (EPSPs).
What type of response do NMDA receptors illicit?
Slower response.
What ions do NMDA receptors pass upon activation?
Sodium, potassium, calcium.
What ions are implicated in LTP, LTD, excitotoxicity, seizures, and neurodegeneration?
Calcium.
What substances block the NMDA channel?
Magnesium ions, phencyclidine, ketamine, MK801. Zinc also acts as a channel and receptor blocker.
What is the endogenous blocker of the NMDAR channel?
Magnesium.
What neurotransmitter must occupy its site on the NMDAR for activation to occur?
Glycine.
