Receptors Masterlist Flashcards
What are the 3 ionotropic (S)-Glutamate receptors
NMDA, AMPA, Kainate
How many types of metabotropic Glutamate receptors are there
8
What are the Group 1 metabotropic glutamate receptors
mGlu1 and 5
What G protein is coupled to Group 1 metabotropic glutamate receptors
G(alphaq)
What are the Group 2 metabotropic glutamate receptors
mGlu2 and 3
What G protein is coupled to Group 2 metabotropic glutamate receptors
G(alphai/o)
What are the Group 3 metabotropic glutamate receptors
mGlu4, 6, 7, 8
What G protein is coupled to Group 3 metabotropic glutamate receptors
G(alphai/o)
Where are ionotropic glutamate receptors located
post-synaptic
How many subunits make up the ionotropic glutamate receptors
4 - tetrameric assembly
What are the subunits in an AMPAR
GluA1-4
What is the make-up of an AMPAR
receptors can form homomers or heteromers
What are the subunits in a Kainate receptor
GluK1-5
What is the make-up of Kainic receptors
GluK1-3 can form homomers. GluK4 and GluK5 can only form functional receptors as heteromers with GluK1-3
Which receptor contains a Q/R site
AMPARs
What is the Q/R site responsible for
Modulating receptor permeability to calcium and sodium ions
Under what conditions is an AMPAR permeable to calcium and sodium ions
When glutamine is bound to the receptor
Under what conditions is an AMPAR not permeable to ions
When arginine is bound to the receptor
Where is the amino terminal domain located
extracellular
Where is the carboxy terminal domain located
intracellular
What does the amino terminal domain contain
Negative allosteric modulator binding site
What are the subunits in NMDARs
GluN1 and GluN2A-D
What is the most common make-up of NMDARs
2xGluN1 + 2xGluN2
What are the 3 important properties of NMDARs
- highly permeable to calcium ions
- channel blocked by magnesium ions
- glycine is a necessary co-agonist with glutamate
What are the conditions for NMDA channel blocking
Mg2+ can only block the channel when both glutamate and glycine are bound
How is NMDA channel blocking released
AMPA activation
Where does glycine bind on the NMDAR
GluN2
Where does glutamate bind on NMDARs
GluN1
What is an example of a negative allosteric modulator which binds to NMDARs
eliprodil - anticonvulsant
Where is site C located in the NMDAR
in the transmembrane domain
What is site C in the NMDAR
channel blocker binding site
What is the role of NMDARs
mediate slow excitatory post-synaptic response via calcium and sodium entry
What are the 2 types of GABA receptors
GABAA and GABAB
What type of receptor is GABAA
ligand-gated ion channel
What does GABAA do when activated
allows entry of chloride ions into neurones
Where are GABAA receptors located
post-synaptic
How many subunits do GABAA receptors have
5 - pentameric
What are all the different subunits of GABAA receptors
6alpha, 3beta and 3gamma
What is the most common combination of GABAA receptors
2alpha, 2beta and 1gamma
What binds to the alpha-beta interface in the GABAA receptor
GABA agonists and competitive antagonists
Where do benzodiazepines bind on the GABAA receptor
alpha-gamma interface
What other compounds bind at the GABAA receptor
barbiturates. general anaesthetics, neurosteroids, ethanol
What blocks the GABAA channel pore
Picrotoxin
What are the subunits of GABAB receptors
GABAB1 and GABAB2
What type of G-protein is coupled to GABAB receptors
Gi/o
What are the effects of GABAB receptor activation
- Increased K+ output
- Decreased Ca2+ uptake
- decreased cAMP -> increase PKA
How does GABAB receptor activation affect transmitter release presynaptically
inhibiting voltage-gated calcium channels
How does GABAB receptor activation affect postsynaptic excitability
reduces postsynaptic excitability by increasing potassium output
What receptor does noradrenaline bind to
alpha and beta adrenoceptors
What are the subtypes of receptors which noradrenaline act on
alpha1, 2 and beta1-4
What beta-adrenoceptors are present in the CNS
beta 1 and 2
Are adrenoceptors ionotropic or metabotropic
metabotropic
What G-protein is coupled to alpha1-adrenoceptors
Gq
What G-protein is coupled to alpha2-adrenoceptors
Gi/o
What G-protein is coupled to beta-adrenoceptors
Gs
Where are alpha1-adrenoceptors located
post-synaptic
Where are alpha2-adrenoceptors located
pre and post-synaptic
Where are beta-adrenoceptors located
pre and post-synaptic
What are the 2 receptor families that are acted on by dopamine
D1 and D2
Are dopamine receptors ionotropic or metabotropic
metabotropic
What receptors are included in the D1 family of dopamine receptors
D1 and D5
What receptors are included in the D2 family of dopamine receptors
D2, 3 and 4
Where are D1-family dopamine receptors located
post-synaptic
Where are D2-family dopamine receptors located
pre and post-synaptic
How many serotonin receptor subtypes are there
7
Which 5-HT receptors are metabotropic
5-HT1, 2, 4-7
Which 5-HT receptors are ionotropic
5-HT3
What G-protein is coupled to 5-HT1 receptors
Gi/o
What G-protein is coupled to 5-HT2 receptors
Gq
Where and how do 5-HT1 receptors act
pre and post-synaptic inhibition
Where and how do 5-HT2 receptors act
post-synaptic excitation
Where do 5-HT3 receptors act
post-synaptic
Where do 5-HT4-7 receptors act
post-synaptic
What does 5-HT1 receptor activation affect
mood (A)
What does 5-HT2 receptor activation affect
behaviour (A/C), sleep, mood, anxiety
What does 5-HT3 receptor activation affect
anti-emetic, mood, anxiety, nausea
What are the 2 types of cholinergic receptors
nicotinic and muscarinic
How many subunits are in a nicotinic acetylcholine receptor
5 - pentameric
Are nAChRs ionotropic or metabotropic
ionotropic
What are the nAChR subunits
alpha2-7, alpha9, alpha10, beta2-4
What is the most common assembly of heteromeric nAChRs
2alpha4 + 3beta2
What is the most common assembly of homomeric nAChRs
alpha7
What are the effects of nAChRs
mediate effects of nicotine including arousal, enhanced learning and memory
Are mAChRs ionotropic or metabotropic
metabotropic
What are the main excitatory mAChR subtypes
M1, 3 and 5 (M1 family)
What G-protein is coupled to the M1 family of mAChRs
Gq
What are the effects of M1 family mAChR activation
activation leads to excitation through modulation of M-type K+ channels
What are the inhibitory subtypes of mAChRs
M2 and M4
What G-protein is coupled to M2 and M4 mAChRs
Gi/o
What are the 5 classical opioid receptors
mu, delta, kappa, ORL1 and nociceptin
Are opioid receptor ionotropic or metabotropic
metabotropic
What G-protein is coupled to opioid receptors
Gi/o
What are the presynaptic effects of opioid receptor activation
inhibit transmitter (glutamate and substance P) release through inhibition of calcium channels
What are the postsynaptic effects of opioid receptor activation
inhibit neuronal firing through activation of potassium channels
How do opioid receptors cause excitation
disinhibition in the ventral tegmental area (VTA) -> enhances dopamine release in the nucleus accumbens
What are the main effects of mu opioid receptor activation
analgesia, euphoria, respiratory depression, constipation
What are the main effects of delta opioid receptor activation
analgesia, dysphoria, diuresis
What are the main effects of kappa opioid receptor activation
analgesia, antidepressant, proconvulsant
What are the Cannabinoid receptor subtypes
CB1 and CB2
Are cannabinoid receptors ionotropic or metabotropic
metabotropic
What G-protein is coupled to cannabinoid receptors
Gi/o
Where are CB1 receptors located
high expression in CNS, high density in cortex and basal ganglia
Where are CB2 receptors located
lymphoid tissue, immune cells
