GPCRs 2

Question 1

What does PKA in the heart do?

Answer 1

Phosphorylates VOCCs

which increases their activity

Question 2

What are the effects of increased VOCC activity in the heart?

Answer 2

Increased calcium ion influx into the cell
increased contractility
positive inotropic effect

Question 3

What does inotropy mean?

Answer 3

Force of contraction

Question 4

What types of GPCRs are located in presynaptic neurones in the CNS and PNS?

Answer 4

M-opioid GPCRs

Question 5

What type of G-protein are M-opioid GPCRs coupled to?

Answer 5

Gi

Question 6

What effect do activated M-opioid receptors have on pre-synaptic neurones in the CNS and PNS?

Answer 6

Reduce neurotransmitter release

Question 7

How do activated M-opioid receptors on pre-synaptic neurones in the CNS and PNS reduce neurotransmitter release?

Answer 7

Free beta-gamma subunit binds to VOCCs

inhibits calcium ion influx

Question 8

What are the types of GPCRs located in the heart?

Answer 8

M2

B1

Question 9

Where are M2 receptors in the heart located?

Answer 9

SA node

AV node

Question 10

What is the outcome of activation of the different M2 receptors in the heart?

Answer 10

SA node - negative chronotropy

AV node - reduced cardiac conduction velocity

Question 11

Where are B1 adrenoceptors located in the heart?

Answer 11

SA node

Ventricles

Question 12

What is the outcome of activation of the different B1 adrenoceptors in the heart?

Answer 12

SA node - positive chronotropy

Ventricles - positive inotropy

Question 13

What does chronotropy mean?

Answer 13

Heart rate

Question 14

What are the types of GPCRs located in vascular smooth muscle?

Answer 14

A1

B2

Question 15

What is the outcome of activation of A1 adrenoceptors in vascular smooth muscle?

Answer 15

Vasoconstriction

Question 16

What is the outcome of activation of B2 adrenoceptors in vascular smooth muscle?

Answer 16

Vasodilation

Question 17

What are the types of GPCRs located in bronchiolar smooth muscle?

Answer 17

M3

B2

Question 18

What is the outcome of activation of M3 receptors in bronchiolar smooth muscle?

Answer 18

Bronchoconstriction

Question 19

What is the outcome of activation of B2 adrenoceptors in bronchiolar smooth muscle?

Answer 19

Bronchodilation

Question 20

What are the types of GPCRs located in intestinal smooth muscle?

Answer 20

M3

B2

Question 21

What is the outcome of activation of M3 receptors in intestinal smooth muscle?

Answer 21

Contraction of smooth muscle

giving increased motility

Question 22

What is the outcome of activation of B2 adrenoceptors in intestinal smooth muscle?

Answer 22

Relaxation of smooth muscle

decreased motility

Question 23

What are the types of GPCRs located in bladder smooth muscle?

Answer 23

M3

B2

Question 24

What is the outcome of activation of M3 receptors in bladder smooth muscle?

Answer 24

Contraction of bladder detrusor muscles
relaxation of sphincter muscles
giving passing of urine

Question 25

What is the outcome of activation of B2 adrenoceptors in bladder smooth muscle?

Answer 25

Bladder sphincter muscle contracts | urine is contained in bladder