Drugs affecting vasculature and blood pressure

Question 1

Myosin light chain phosphate

Answer 1

Causes contraction

Question 2

Role of nitric oxide in relxation?

Answer 2

Nitric oxide
Increase guanylate cylcase 
= increased cGMP 
= increased activity of protein kinase G
= relxation

Question 3

Nitrates, veno or arterial dilation?

Answer 3

Small venodilation
Big arteriolar dilatation (reduces pulse wave reflection)
In coronary blood flow, there is no overall increase but blood is redirected towards the ischemic zone

Question 4

Side effects of GTN/isosorbide mononitrate?

Answer 4

repeated administration of organic nitrates may be associated with a diminished effect (tolerance – can be minimised by ‘nitrate low’ periods)

headaches may occur initially

Question 5

Endothelin antagonists and their use?

Answer 5

Bosentan. ambrisentan

-used in pulmonary hypertension

Question 6

Where would you find ACE?

Answer 6

Membrane bound enzyme on the surface of endothelial cells

Question 7

Adverse effects of ACEi’s?

Answer 7

May initially cause hypotension (esp. in patients treated with diuretics)
Dry cough

Question 8

What does ACE do?

Answer 8

Converts inactive angiotensin I to angiotensin II (vasoconstrictor)
Inactivates bradykinin (vasodilator)