Beta Blockers

Question 1

Where are Beta adrenergic receptors found in the heart

Answer 1

Beta 1 and 2 receptors are found in the sinoatrial node, in ectopic pacemakers, and also in contractile muscle fibers.
Beta 2 by itself is found in skeletal muscle vessels and is responsible for relaxing skeletal muscle.

Question 2

What is the relationship between beta blockers and the JGA in the kidney

Answer 2

Beta receptors on the JGA stimulate the release of renin when activated. beta blockers therefore block renin release

Question 3

What are the effects of Beta blockers on norepinephrine and epinephrine actions

Answer 3

Beta blockers do nothing to the action of norep and ep

Question 4

Beta blockers prevent isoproteronol from having an effect

Answer 4

true

Question 5

First Beta Blocker and is it specific or nonspecific

Answer 5

Propanolol, Non-specific

Question 6

Esmolol, whats so special about it

Answer 6

Ridiculously short half life (.15) which allows you to have very close control of drug levels.

Question 7

Main beta blockers with membrane stabilizing activity

Answer 7

Propanolol, Acebutolol, Carvedilol

Question 8

What is the mechanism of the membrane stabilizers

Answer 8

Bind and block fast Na channels which are responsible for the rapid depolarization of cardiac potentials. Decreases the amplitude of action potentials

Question 9

ISA

Answer 9

intrinsic sympathomimetic activity

Question 10

ISA drugs?

Answer 10

Pindolol and acebutolol

Question 11

What does ISA mean they can do?

Answer 11

These drugs can stimulate the heart to provide relief from bradycardia (slow heart rate..under 60).

Question 12

Pure sympathetic antagonist

Answer 12

propanolol

Question 13

Beta blockers that have extended action as Alpha one receptor antagonists

Answer 13

Carvedilol, Labetalol

Question 14

Antagonists with extended action as Calcium entry blockers

Answer 14

Carvedilol and betaxolol

Question 15

Antagonists with extended action as nitric oxide producers

Answer 15

Cartelol, Nebivolol

Question 16

Beta blockers don’t reduce bp in normotensive pts but do so in pts with hypertension

Answer 16

true

Question 17

What Beta blocker is used to decrease renin when renin is elevated

Answer 17

propanolol

Question 18

What drug has no effect on renin release

Answer 18

Pindolol

Question 19

Long term effects of beta blockers?

Answer 19

Decrease vascular resistance

Question 20

Beta blockers and CHF

Answer 20

BBs may lead to CHF in pts with predisposing heart conditions

Question 21

BBs and bradycardia

Answer 21

Can be a problem in pts wth AV node conduction defects

Question 22

BBs can lead to cold extremities from decreased peripheral vascular flow

Answer 22

true

Question 23

When coming off a beta blocker should the dose be decreased gradually or abruptly

Answer 23

Gradually. Abrupt stoppage after long-term treatment can lead to angina and increase risk of death.

Question 24

Off target pulmonary effects

Answer 24

Blockade of bronchial smooth muscle beta 2 receptors can lead to bronchoconstriction and life threatening airway resistance in pts with bronchospastic disease

Question 25

What drugs to use with pts who have bronchospasm disease

Answer 25

beta 1 selective drugs or those with ISA

Question 26

Off target CNS effects?

Answer 26

Can lead to mental disorders, fatigue, vivid dreams

Question 27

Off target glucose effects

Answer 27

Beta 2 adreno receptors usually stimulate hepatic glycogen breakdown and glucagon release. BBs can lead to hypoglycemia/
Also….in diabetics, Beta Blockers may mask the tachycardia that is a warning sign for insulin induced hypoglycemia

Question 28

Off target lipid profile effects

Answer 28

Increase triglycerides and decrease HDLs

Question 29

Primary clinical uses of beta blockers

Answer 29

Hypertension, Acute MI

Non CV: Tremor, thyrotoxicosis, anxiety, prophylaxis of migraine, prevention of bleeding, treatment of glaucoma