Calcium channel blockers Flashcards Preview

Pharm Exam 3 > Calcium channel blockers > Flashcards

Flashcards in Calcium channel blockers Deck (54):
1

What is the more determining factor for ion flow? Concentration gradient or Electrical gradient?

Electrical Gradient

2

Where is K more highly concentrated?

Inside the cell

3

Where is K more lowly concentrated?

Outside the cell

4

Where is Na low?

Inside the cell

5

Where is Na high?

Outside

6

Ca+ is low where?

Inside the cell

7

Ca+ is high where?

Outside the cell

8

Most important Ca voltage gate you need to know for this class?

L-type, Ca 1.2

9

What triggers contraction of Ca 1.2?

Ca2+ entry

10

Ca 1.2 is found on what?

Cardiac and smooth muscle

11

Ca 1.3 is found where?

SA/AV nodes, neurons, and endocrine cells

12

What is a Ca1.3 a trigger for?

Hormone secretion

13

Blockage of vascular smooth muscle leads to what?

Vasodilation

14

Block of channels in cardiac muscle and SA/AV node results in what benefit?

Anti-arrhythmic

15

What are intracellular stores of Ca2+ called?

RYR@ (ryanodine receptor 2)

16

What REQUIRES Ca2+?

Cardiac and smooth muscle contraction

17

What does Ca2+ release from SR bind to?

Troponin C

18

Ca2+ binding of troponin c leads to what?

Displacement of tropomyosin

19

Displacement of Tropomyosin causes what?

Allows myosin to bind actin

20

What coupling allows for skeletal muscle contraction?

Coupling between Ca 1.1 and RYR1

21

Does skeletal muscle contraction require extracellular Ca2+?

No

22

Clinical applications for Calcium channel blockers? (3)

Angina Pectoris
Arrhythmia
Hypertension

23

3 Distinct Chemical Classes of Calcium Channel blockers?

Dihydropyridines
Phenylalkylamines
Benzothiazepines

24

Main structural feature of Dihydropyridines?

Dihydropyridine ring

25

+ enantiomer of DHP does what?

Keeps gate closed and blocks current

26

- enantiomer of DHP does what?

Won't let gate close and keeps current going

27

When do you give Clevidipine?

When you want to treat hypertension immediately and oral administration isn't possible.

28

What do you have to watch out for when giving clevidipine?

Allergy to soy and egg

29

Where are DHPs most potent?

Relaxing smooth muscle such as coronary artery

30

Do DHPs compromise cardiac function?

No

31

DHPs are dependent on what for their potency?

Voltage of membrane

32

Binding sites for DHPs, PAAs, and BZPs are what?

Linked, but not identical

33

Characteristics of DHP block?

No frequency dependence
Marked tonic block

34

What effects does DHP have on vascular system (3)?

Decrease in peripheral resistance
Decreased after load
Little effect on HR or contraction

35

Drug listed in packet that has the least vascular specificity?

Nifedipine

36

Drug used in cases of sub arachnoid hemorrhage to prevent neuropathy?

Nimodipine

37

Secondary result of DHPs on the heart?

Reflex tachycardia except for amlodipine

38

How do DHPs reduce angina?

They lower the oxygen demand of the heart

39

Which DHP does depress cardiac function?

Nifedipine

40

Why is Amlodipine the most commonly prescribed calcium channel blocker?

It has slow onset and long duration of action

41

Phenylalkylamine (PAAs) cause what?

Vasodilation, less potent than DHP

42

Effect of PAA on SA and AV node?

Slows conduction through SA and AV node to reduce heart rate and force of contraction

43

How severe is the reflex tachycardia from PAA?

Blunted

44

Characteristics of PAA block?

Marked frequency dependence
Very little tonic block

45

Benzothiazepine affects the heart how?

Vasodilation, slows conduction, reflex tachycardia, but inhibits less than verapamil but more than DHPs

46

Characteristics of BZP block?

Some tonic block
Some frequency block

47

Of the three types of drugs discussed which affects heart rate the most?

Verapamil

48

Of the three types of drugs discussed which affects AV conductance/Myocardial contraction the most?

Verapamil

49

Of the three drugs listed which affects arterial vasodilation the most?

DHPs

50

Most important side effects of calcium channel blockers?

Ankle edema
Constipation
Facial flushing
Tachycardia

51

Which class of drug causes the most constipation?

Verapamil

52

Which class of drug causes the most facial flush/

DHPs

53

Which class of drugs causes the most tachycardia?

DHPs

54

Danger surrounding prompt release nifedipine?

Increased risk of subsequent heart attack due to reflex sympathetic response tachycardia