12 Vasodilator Pharmacology

Question 1

What are indirect vasodilators?

Answer 1

drugs which block vasoconstriction

Question 2

What are the 2 targets for indirect vasodilators?

Answer 2

ANS

RAAS

Question 3

How can we target the ANS for indirect vasodilation?

Answer 3

sympathetic blockade

alpha 1 receptor blockers

Question 4

How can we target the RAAS for indirect vasodilation?

Answer 4

angiotensin II is a vasoconstrictor

Question 5

How does cGMP affect smooth muscle function?

Answer 5

affects Ca2+ channel opening duration

hence affects myosin : actin interaction

Question 6

Name 6 potential uses of direct vasodilators

Answer 6

Hypertension
Angina Pectoris
Peripheral Vascular Disease
Impotence
Hair loss
Cerebral function

Question 7

What are the 3 types of treatment for angina pectoris?

Answer 7

1 - not vasodilators
2 - organic nitrates
3 - Ca2+ channel blockers

Question 8

Name 2 drugs used to treat angina pectoris which aren’t vasodilators

Answer 8

beta blockers

ivabradine

Question 9

Name the most common form of organic nitrate

Answer 9

Glyceryl Trinitrate (GTN)

Question 10

What is the MOA of GTN?

Answer 10

broken into NO
NO activates guanylate cyclase
increases cGMP
decreases venous return
dcreases cardiac work
decreases oxygen demand

Question 11

What are the unwanted effects of GTN?

Answer 11

XS vasodilation…
hypotension (syncope and reflec tachycardia)
headache
constipation

Question 12

Why is GTN not administered orally?

Answer 12

it is wiped out by 1st pass metabolism baby

Question 13

What are the 2 main methods for GTN administration?

Answer 13

Sublingual

Tansdermal for phrophylaxis

Question 14

What are the benefits of sublingual GTN?

Answer 14

easy, everyone knows where their mouth is

people can take it on a need-to basis

Question 15

What are the therapeutic issues associated with GTN?

Answer 15

Physiological tolerance

Pharmacological tolerance

Question 16

What is physiological tolerance?

Answer 16

other factors / mechanisms counteract the pharmacologcial effect

Question 17

What is pharmacological tolerance?

Answer 17

fundamental change in MOA

Question 18

What is the main group of calcium channel blockers used to treat angina called?

Answer 18

Dihydropyridines (DHPs)

Question 19

What is the most common form of DHP?

Answer 19

Amlodipine

Question 20

What tissue type do DHPs focus on?

Answer 20

vasculature

Question 21

What is the overwhelming action of DHPs?

Answer 21

systemic vasodilation affecting afterload

Question 22

What unwanted effects are associated with DHPs?

Answer 22

flushing

decreased GIT activity

Question 23

What are the features of Raynaud’s Syndrome?

Answer 23

vascular spasm induced by cold weather

very painful

Question 24

Which drug to we have to be cautious around when treating Raynauds Synrome?

Answer 24

Nifedipine (DHP), as it doesn’t always work

Question 25

How is erection usually controlled?

Answer 25

NO -> cGMP

Question 26

What is the MOA of Sildenafil?

Answer 26

PDE - type 5 inhibitor

this is specific to genital tissues

Question 27

What interaction is important for sildenafil?

Answer 27

can itneract with other nitrate and be fatal

important to consider with vascular diseases!

Question 28

What vasodilator is used to treat hair loss?

Answer 28

Minoxidil (Regaine)

Question 29

What is the MOA of Minoxidil?

Answer 29

K+ channel opening
K+ efflux
hyperpolarisation
Ca2+ VGCs don’t open