Vasodilators

Question 1

LB: Inhibition of L-type calcium channels causes

Answer 1

Decreased HR (lower SA firing)
AV velocity block
Decreased contractility of cardiovascular muscles

Question 2

LB: Rank the effectiveness of the three calcium channel blockers on L-type calcium channels

Answer 2

Verapamil>Diltiazem>Amlodipine

Question 3

LB: On what two phases of the cardiomyosite cycle do the calcium channel blockers have their effects

Answer 3

Phase 0 (decreases SA firing rate)
Phase 2 (Plateau, reduces Myocyte contractility)

Question 4

LB: ***What are the side effects of calcium channel blockers, and which drug has a higher incidence of each?

Answer 4

Hypotension - Amlodopine
CHF - Verapamil
AV Block - Verapamil
Edema - Amlodopine
Constipation - Amlodopine
Headaches - Verapamil

Question 5

LB: What is the most commonly used K-channel opener and what does it target?

Answer 5

Minoxidil - Very potent arterial vasodilator, results in compensatory increase in HR and cardiac output, as well as fluid retention.

Question 6

LB: What is an interesting alternative use of minoxidil?

Answer 6

It can be used to treat male pattern baldness because a side effect is hypertrichosis (Rogaine)

Question 7

LB: Guanylyl Cyclase activators have what mechanism of action?

Answer 7

Increase production of cGMP, which results in ***equal venodilation and arteriodilation.

Question 8

LB: What is the net effect of guanylyl cyclase activators?

Answer 8

Decrease of TPR and Cardiac Output, causing a decrease in BP and compensatory increase in HR

Question 9

LB: Which guanylyl cyclase activator class can not be given P.O.?

Answer 9

Nitroprussides

Question 10

LB: What type of calcium channel blocker has the largest vasodilator effect, and what type of vessel does this have the most effect?

Answer 10

DHPs (like Amlodipine) - Arteriodilation

Question 11

LB: Organic nitrates effect both types of blood vessels. What types of blood vessels are dilated in low and in high doses?

Answer 11

Low doses will cause venodilation, high doses will add arteriodilation effects as well. HR increases as compensation in both cases.

Question 12

LB: Aside from hypotension, what is an important factor to keep in mind when prescribing organic nitrates?

Answer 12

Patients can develop a tolerance - only use it for certain parts of the day (patch on during day, patch off at night)

Question 13

LB: What route is Nitric Oxide given?

Answer 13

Inhalational, results in very low half life (3-6 seconds)

Question 14

LB: The guanylyl cyclase activator hydralazine has a unique side effect:

Answer 14

ANA: A lupus like syndrome that is reversible on cessation of the medicine. More common at higher doses and in slow acetylators

Question 15

LB: Fenoldopam is what class of drug and has what effects

Answer 15

D1 receptor agonist that causes decreased BP and increased HR. Given IV.

Question 16

LB: Sildenafil, Vardenafil, and Tadalifil

Answer 16

Inhibit PDE type 5 resulting in vasodilation, can aid in erection

Question 17

LB: Sudenafil, vardenafil, and tadalifil should be used in care with patients who use what drugs?

Answer 17

Beta blockers
Organic nitrates
CYP3A4 interacting drugs

Question 18

LB: ACE inhibitors inhibit the production of what, and cause what net effects on the body?

Answer 18

Decreased angiotensin II leading to decreased TPR, decreased sodium and fluid retention, decreased BP, and increased HR

Question 19

LB: What are adverse effects of inhibitors to the renin/angiotensin/aldosterone system?

Answer 19

Hyperkalemia
***Fetotoxicity
Hypersensitivity

Question 20

LB: What side effect is common with all Vasodilators?

Answer 20

Hypotension

Question 21

LB: When using an ACE Inhibitor, a patient sometimes has a dry cough. What causes this dry cough and what can you use to avoid it?

Answer 21

Bradykinin can lead to a cough, and blocking of ACE can lead to increased bradykinin concentrations

Question 22

LB: What three diseases are Vasodilators and inhibitors of the renin/angiotensin/aldosterone system generally used for?

Answer 22

CHF
Hypertension
Angina/Ischemia

Question 23

LB: What class of R/A/A effective drugs effects each part of the Renin/Angiotensin/Aldosterone pathway?

Answer 23

Angiotensinogen -> Angiotensin I - Aliskirin (Renin inhibitor)
Angiotensin I -> Angiotensin II - ACE Inhibitor
Angiotensin II receptors in body - AT-Receptor antagonists

Question 24

LB: Match the drug or suffix to the drug class:
AT-Antagonist—————————————————Verapamil
Calcium channel blocker (dihydropyridine)—————Aliskirin
Calcium channel blocker (non-dihydropyridine)———Amlodipine
ACE Inhibitor—————————————————-Nitro
Phosphodiesterase inhibitor———————————(lo)sartan
Renin inhibitor—————————————————(lisin)opril
K channel blocker———————————————-(tadal)afil
Guanylyl cyclase activator————————————Minoxidil

Answer 24

AT-Antagonist—————————————————(lo)sartan
Calcium channel blocker (dihydropyridine)—————Amlodipine
Calcium channel blocker (non-dihydropyridine)———Verapamil
ACE Inhibitor—————————————————-(lisin)opril
Phosphodiesterase inhibitor———————————(tadal)afil
Renin inhibitor—————————————————Aliskirin
K channel blocker———————————————-Minoxidil
Guanylyl cyclase activator————————————nitro