L.8 Flashcards
What are the three types of ionotropic glutamate receptors?
- NMDA receptors
- AMPA receptors
- Kainate receptors
What is the agonist for NMDA receptors?
NMDA
What is the antagonist for NMDA receptors?
APV drug
What is the agonist for AMPA receptors?
AMPA
What is the antagonist for AMPA receptors?
CNQX drug
What is the agonist for Kainate receptors?
Kainaic acid
What is the antagonist for Kainate receptors?
CNXQ drug
Outline how Non-NMDA Receptors work?
- gluatamte binds to Non-NMDA receptor (activates them)
- when receptors are activated –> ion channels open
- Na+ flow in and K+ flow out
- Na+ influx (more positive)
- EPSP
Outline how NMDA receptors work
- glutamate & glycine must bind to NMDA receptor
- Mg2+ blocks receptor at resting state
- neuron needs to be depolarised to removed Mg2+
- Once Mg2+ is removed, NMDA receptors open = Ca2+ in and K+ out
- Ca2+ acts as secondary messenger causing intracellular processes
What is the role of NMDA receptors in LTP?
- Ca2+ influx is important for synaptic plasticity & long-term potentiation (learning & memory)
What is late EPSP in NMDA receptors
- open more slowly + stay open for longer
- allows a longer-lasting signal
- good for synaptic plasticity & LTP
TRUE or FALSE: NMDA receptors are metabotropic (+ why)
- FALSE (ionotropic)
- they don’t use G-coupled proteins
TRUE or FALSE: Non-NMDA receptors are early-phase EPSP
TRUE
What is the result of too little GABA in the nervous system?
Seizures or muscle spasms due to lack of inhibitory control
What happens when there is too much GABA?
Loss of consciousness and coma
What is the function of the GABAergic system?
Inhibitory signaling to prevent over-excitation
What are the 2 main consequences of NMDA receptors dysregulation
- Schizophrenia
- glutamate excitotoxicity
What is glutamate excitotoxicity
too much glutamate overstimulates neurons
What causes glutamate excitotoxicity to happen
- NMDA receptors are overactivated
- excess Ca2+ influx
What are the effects of glutamate excitotoxicity
- cell damage
- stroke
- seizures
How can NMDA receptors cause Schizophrenia effects
- NMDA receptors are inhibited by PCP
- causes hallucinations like in Schizophrenia
What are the 2 main types of GABA receptors
- GABA ionotropic receptors (GABA A)
- GABA metabotropic receptors (GABA B)
What are the features of GABA ionotropic receptors
- ligand-gated Cl- channels
- fast/early IPSP
What are the features of GABA metabotropic receptors
- G-protein coupled receptors
- slow/late IPSP
- K+ and Ca2+