Memory modulation: AMPA & NMDA receptors Flashcards
Name the 3 types of ionotropic glutamate receptor channels?
- NMDA
- AMPA
- Kainate
Name the 7 individual NMDA receptors?
GluN1
GluN2A
GluN2b
GluN2C
GluN2D
GluN3A
GluN3B
Name the 4 AMPA receptors?
GluA1
GluA2
GluA3
GluA4
Name the 5 Kainate receptors?
GluK1
GluK2
GluK3
GluK4
GluK5
AMPA receptors?
Conduct sodium
Activated by AMPA, glutamate.
Blocked by CNQX.
Mediates fast excitatory synaptic transmission
Implications for learning and memory
NMDA receptor?
Conduct calcium
Blocked by magnesium.
Glucine or D-serin is a co-agonist
Blocked by APV.
Ionotropic Glutamate Receptor Channels- endogenous agonists
AMPAR: Glutamic acid, AMPA
KAR: Glutamic acid, Kainic acid
NMDAR: Glutamic acid, NMDA
What is required for the activation of NMDA receptors?
Requires the binding of glutamate and the binding of the co-agonist glycine (or D-serine)
Synergistic interplau of synpatic AMPA receptors & NMDA receptors?
Neurally released glutamte activates synaptic AMPA receptor, even though glutamate also binds to NMDA it doesnt initially conduct due to the blockage of magnesium.
The sodium influx causes by the AMPA causes a depolarisation. This depolarisation causes the magnesium to unblock the NMDA- now appears a slow synpatic depolarisation.
What happens when you block NMDA receptor in rodent models?
Block learning and memory.
Morris water maze to test spatial memory.
NMDA receptor role during learning.
The rodents are still learning however are not learning as fast as the groups without the blockage of these receptors.
DL-APS?
Potent antagonist of the NMDA receptor
NMDA role in memory?
Important for memory retrieval.
NMDAr bloackade by?
AP5
Affects spatial learning and memory
AP5 has no effects on?
Visual or motor impairments which could cause the cognitive deficits
D-L AP5?
Causes cognitive deficits
DLAP5 > LAP5?
Caused changes in synaptic long term potentiaion.
LAP5 is active but less potent
The catergorisation of long term memory?
AS4
Episodic memory?
Memory for unique events experienced in our daily lives.
What, where, when, who,…
Spontaneously remembered information.
Thought to be processed by the hippocampal region
Paired associate learning in humans?
Paris of items are studies.
Word pair first eg. aeroplane- ball
Later on, get shown a picture of ball and must recall aeroplane.
Early diagnostic test for AD.
Paired associate learning in rats?
Food flavours and locations.
Foraging animals.
Give them a piece of food and open one arm with the food inside.
Do the same with other flavours.
Then give me a particular flavour and open all arms- should learn to go to the right arm.
CNQX and ap5?
Block learning and new paired associate.
Inhibit transmission from hippocampus by CNQX- blocks AMPA.
CNQX?
Blocks recall of learned paired associates.
to test this: learn the two pair associatio nand then inject them with CNQX.
What glutamate channels does CNQX block?
NMPA and AMPA
CNQXs blocks AMPArs therefore?
Blocks fast synpatic transmission
AP5 blocks NMDARS therefore?
Blocks long term potentiation
AMPA channel is used for?
Fast synaptic transmission
Activates NMDA
NMDA is used for?
long term potentiation.
It is only activated by the depolarisation of the cell (due to activation of AMPA)
Both are needed
What two glutamate channels are required for paired associate learning?
AMPA
NMDA
What channel(s) are required for recall?
Only AMPA
