GABA Receptors

Question 1

What type of receptor is the GABA-a receptor?

Answer 1

Ionotropic

Question 2

What type of receptor is the GABA-b receptor?

Answer 2

Metabotropic GPCR

Question 3

How many subunits does the GABA-a receptor have?

Answer 3

5

Question 4

What are the possible subunits of the GABA-a receptor?

Answer 4

19 possible subunits
Alpha, Beta, Gamma, Delta and Phi types
Must contain at least one alpha subunit

Question 5

How many domains does the GABA-a receptor subunits have?

Answer 5

Each subunit has 4 transmembrane domains

Question 6

Where are GABA-a receptors located?

Answer 6

Postsynaptically

Question 7

Where are GABA-b receptors located?

Answer 7

Presynaptically

Postsynaptically

Question 8

What are the effects of the GABA-a receptor?

Answer 8

Chloride ion influx

Neuron hyperpolarisation

Question 9

What are the effects of the GABA-b receptor?

Answer 9

Reduced cAMP signalling and inhibition of Sodium channels and VOCCs, less neurotransmitter release
Opening of GIRK potasisum channels allowing potassium efflux and hyperpolarisation

Question 10

Name 4 compounds that can positively allosterically modulate GABA-a receptors?

Answer 10

Benzodiazepines
Alcohol
Barbiturates
Neurosteroids