GPCRs

Question 1

What types of G alpha sub units can you get?

Answer 1

Alpha i (inhibitory), alpha s (stimulatory), alpha q

Question 2

What effector does an alpha s sub unit act on?

Answer 2

Acts on adenylyl cylclase, it stimulates its activity to increase conversion of ATP to cAMP, thus increasing cell activity.

Question 3

What effector does an alpha i sub unit act on?

Answer 3

Acts on adenylyl cyclase, inhibiting its activity, decreasing the amount of ATP converted to cAMP, thus reducing cell activity.

Question 4

List some characteristics of GPCR’s

Answer 4

7 transmembrane domains, single polypeptide chain, N terminus extracellular, C terminus intracellular.

Question 5

In the sympathetic nervous system, what is released from the pre and post ganglionic neurones?

Answer 5

Pre: ACh.
Post: NA

Question 6

In the parasympathetic nervous system, what is released from pre and post ganglionic neurones?

Answer 6

Pre and Post both release ACh.

Question 7

In the parasympathetic nervous system, ACh released from pre ganglionic neurones binds to what receptors?

Answer 7

Nicotinic ACh receptors

Question 8

What sub units are present in a G protein?

Answer 8

Alpha, beta, gamma