9: Drugs affecting control of blood pressure

Question 1

In the regulation of vascular smooth muscle tone, calcium enters the cell through which channel?

Answer 1

L-type Ca²⁺ channel

Question 2

What does Ca²⁺ bind to in the process of activating MLCK?

Answer 2

Calmodulin

Question 3

Which enzyme does the calcium-calmodulin complex activate?

Answer 3

MLCK (myosin light chain kinase)

Question 4

What does MLCK do, and what effect does this produce?

Answer 4

Phosphorylates myosin light chains, producing contraction

Question 5

In the process of relaxation in vascular smooth muscle, what enzyme activates myosin-light-chain-phosphatase?

Answer 5

Protein kinase G

Question 6

What activates Protein kinase G, which activates an enzyme during vascular smooth muscle relaxation?

Answer 6

cGMP

Question 7

What does activated Myosin-light-chain-phosphatase do, and what effect does this produce?

Answer 7

Dephosphorylates myosin light chains producing relaxation.