Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Pharmacology Block 2 > 08 Smooth Muscle > Flashcards

08 Smooth Muscle Flashcards

1
Q

Electromechanical Coupling

A
    • operates thru changes in cell membrane potential

- - - 40 to - 70mV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Pharmacomechanical Coupling

A
    • operates independent of cell membrane potential

- - Receptors / Intracellular Signaling

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Mechanism of Smooth Muscle Contraction

A
  • PLC => DG + IP3 (IP3 on SR releases Ca2+)
  • VG Ca2+ channel
  • Myosin Light Chain (MLC) Kinase: when phosphorylated, leads to contraction in actin
  • Rho Kinase: inactivates myosin phosphatase which dephosphorylates MLC

Contraction = actin + MLC(P)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Mechanisms of Smooth Muscle Relaxation

A

Block:

  • VG Ca2+ channel
  • Rho kinase
  • Agonist binding Receptor

Paracrine Factors:

  • NO
  • Dopamine
  • Prostacyclin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Pre-Load

A

Volume of blood in ventricles at end of diastole

Increased in:

  • Hypervolemia
  • Regurgitation of cardiac valves
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Afterload

A

Resistance left ventricle must overcome to circulate blood

Increased in:

  • Hypertension
  • Vasoconstriction

An increase in afterload increases cardiac workload

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is decreased with Nitrates?

A

Pre-load

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the mechanism of action of Nitric Oxide (NO)?

A

NO binds to guanylate cyclase which converts GTP to cGMP

cGMP leads relaxation

Arterial and venous circulation (venous dominant)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Nitroglycerin

A

Organic Nitrate

  • Venous (dominant)

Tx: Heart Failure
Toxicity: Hypotension

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What organic nitrate can be used to treat heart failure?

A

Nitroglycerin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

When using Nitroglycerin, what happens to stroke volume and Left Ventricular End-Diastolic Pressure?

A

LV End-Diastolic Pressure: Dec

SV: No change

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Nitroprusside

A

NO Releasing

Relaxation of arterial and venous circulation

Tx: Hypertensive Emergencies
Toxicity: Hypotension

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What organic nitrate can be used to treat hypertensive emergencies?

A

Nitroprusside

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

When using nitroprusside, what happens to stroke volume and Left Ventricular End-Diastolic Pressure?

A

LV End-Diastolic Pressure: Dec

SV: Inc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Hydralazine

A

Direct Vasodilator

Arterial Circulation

Tx:

  • Heart Failure
  • Severe Hypertension

Toxicity: Hypotension

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

When using hydralazine, where does it work?

A

Directly increases cGMP leading to relaxation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

When using hydralazine, what happens to stroke volume and Left Ventricular End-Diastolic Pressure?

A

LV End-Diastolic Pressure: Dec

SV: Inc

Decreased afterload

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What direct vasodilator can be used to treat heart failure (In combination) or severe hypertension?

A

Hydralazine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Minoxidil

A

Direct Vasodilator

Arterial Circulation
K+ ATP channel opener

Tx:
- severe hypertension

Toxicity: Fluid retenion

20
Q

What direct vasodilator is a K+ ATP channel opener?

21
Q

What direct vasodilator can results in a side effect of fluid retention?

22
Q

Diazoxide

A

Membrane Channel Dilator

K+ Channel Activator (efflux)

Tx: Hypertensive Emergencies

Toxicity: Hypoglycemia

23
Q

What drug is a K+ channel activator used to treat hypertensive emergencies?

24
Q

What membrane channel dilator can have a side effect of hypoglycemia?

25
Ca2+ Channel Blockers
Membrane Channel Dilator Non-selective Arterial circulation Dihydropyridine--nifedipine Phenylalkylamine--verapamil Benzothiazapine--diltazem Blocks contractions in heart and smooth muscle
26
What phosphodiesterases are located in cardiac muscle? smooth muscle?
Heart: PDE3 | Smooth Muscle: PDE3 and PDE5
27
What is the function of phosphodiesterase in cardiac muscle? smooth muscle?
Heart: - PDE3 converts cAMP into AMP, which prevents contraction Smooth muscle: - PDE5 converts cGMP into GMP, preventing relaxation - PDE3 converts cAMP into AMP, which prevents contraction
28
Milrinone, Inamrinone, Cilostazol
Phosphodiesterase (PDE3) inhibitors Located in cardiac and smooth muscle - prevents PDE3 from converting cAMP into AMP - cAMP will activate PKA which will phosphorylate proteins and lead to contraction Tx: Heart Failure
29
What drugs prevents PDE3 from converting cAMP into AMP, therefore creating more forceful contractions for the treatment of heart failure?
Milrinone, Inamrinone, Cilostazol
30
Sildenafil, Tadalafil
Phosphodiesterase (PDE5) inhibitors Located in smooth muscle - prevents PDE5 from converting cGMP into GMP - cGMP results in decreased Ca2+ leading to smooth muscle relaxation Tx: Erectile Dysfunction
31
What drug is used to treat erectile dysfunction?
Sildenafil, Tadalafil PDE5 inhibitors
32
What drug prevents PDE5 from converting cGMP into GMP, resulting in smooth muscle relaxation?
Sildenafil, Tadalafil
33
Renin-Angiotensin Blockers
Smooth muscle dilator 1. Angiotensin Converting Enzyme (ACE) Inhibitors 2. Angiotensin Receptor Blockers 3. Renin Inhibitors 4. Arterial (dominant) and Venous Circulation
34
Fenoldopam
Vasodilator Dopamine 1 Receptor Arterial and Venous Circulation Inc RBF and Na+ Excretion Tx: Hypertensive Crisis
35
What vasodilator drug binds dopamine 1 receptor for the treatment of hypertensive crisis?
Fenoldopam
36
What vasodilator drug increases renal blood flood and Na+ excretion?
Fenoldopam
37
Prazosin
Vasodilator Alpha-adrenergic blocker (prevents NE binding) Arterial and Venous Circulation
38
What drug is an alpha-adrenergic antagonist resulting in vasodilation?
Prazosin
39
Albuterol, Pirbuterol, Terbutaline, Salmeterol, Formoterol
B2 agonist Bronchodilators inc cAMP activates PKA leading to relaxation Toxicity: Tachycardia
40
What B2 agonists can be used for bronchodilation?
Albuterol, Pirbuterol, Terbutaline, Salmeterol, Formoterol
41
What AE can you get from B2 agonists?
Tachycardia
42
Ipratropium, Tiotropium
Anti-cholinergic Bronchodilators Prevents muscarinic receptors from contracting respiratory muscles Mucous secretion
43
What anti-cholinergic drugs can be used as a bronchodilator and to increase mucous secretions?
Ipratropium, Tiotropium
44
Theophylline, Aminophylline
Methylxanthine Bronchodilators - increased mucociliary clearance Phosphodiesterase Inhibition Adenosine Receptor Antagonism
45
What bronchodilator drug can work as a phosphodiesterase inhibitor and/or Adenosine Receptor Antagonist?
Theophylline, Aminophylline

Pharmacology Block 2 (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions