Pharm Adjunct: Beta Blockers concept Flashcards
β agonism results in activation of _____ which then produces _______.
Adenylyl Cyclase (AC)
cAMP
S2
Does Ca⁺⁺ influx or efflux during β agonism?
Influx
S2
What type of receptors are β receptors?
GPCR
S2
What types of β receptors are there and where are they primarily located?
- β1 - Heart
- β2 - Lungs
- β3 - Fat/Muscle
S3
Chronic administration of β blockers results in what effect on receptors?
Receptor upregulation (aka ↑ # of receptors)
After β receptor desensitization from prolonged catecholamine exposure, what drug class can restore receptor responsiveness?
β-blockers
How do β blockers protect myocytes from perioperative ischemia?
By ↓O₂ demand on the heart
T/F. β blockers will potentiate renin release.
false. β blockers will inhibit renin release
decreases C.O.
How will β blockers affect the cardiac foci action potential?
Prolong Phase 4
↓ dysrhythmias during ischemia and reperfusion.
How will β blockers affect diastolic perfusion time?
β blockers will increase diastolic perfusion time.
What type of HTN is a possible indication for β blocker therapy?
Essential Hypertension
Sy
What is SCIP?
Describe the protocol and its goals.
- Surgical Care Improvement Protocol
- β-blockers must be given within 24 hrs of surgery for patients at risk for cardiac ischemia and ones already on β-blocker therapy.
S7
What were the three β1 selective agents discussed in lecture?
- Metoprolol
- Atenolol
- Esmolol
not cause vasodilation
S9
What percentage of β receptors in the myocardium are β1 ?
75%
S9
Do cardio-selective β-blockers cause vasodilation?
No
S9
What type of affinity are Beta-blockers and what happens at high doses?
Selective affinity
Selectivity is lost at high doses of Beta Blockers
S4
What do some Beta blockers do to arterial vascular tone and afterload?
reduce arterial vascular tone and decrease afterload
S5
