Unit 2 - Antihypertensive Flashcards
Lower sodium reabsorption at different sites in the nephron (kidney), thereby increasing urinary sodium and water losses and lowering blood volume and BP.
Diuretics
Decrease the heart rate and cardiac output, which lowers blood pressure and makes the heartbeat both more slowly and with less force.
Beta-Blockers
Mechanism of action inhibits the sympathetic nervous system, blocking catecholamines (epinephrine and norepinephrine) from binding to nerves.
Beta-Blockers
Act on the Heart
Beta 1 Blockers
Act on the Lungs
Beta 2 Blockers
Beta 1 Blockers
Decrease HR and Contractility
Beta 2 Blockers
Peripheral Vasoconstriction and Bronchoconstriction
Alpha Blocker
Peripheral Vasodilation
Medications act on combinations of these receptors to reduce CO and BP
Beta 1, Beta 2, Alpha Blockers
Cardiovascular beneficial effects of Beta-Blockers:
- Decreased blood pressure
- Decreased myocardial oxygen demand
- Decreased water and salt retention
- Decreased oxidative and inflammatory stress
- Attenuated cardiovascular remodeling
Mechanism of Action: Blocks slow calcium channels.
Calcium Channel Blockers
Decrease contractility
Vasodilation
AV Node Slows
Calcium Channel Blockers
Calcium channel blockers inhibit calcium influx into arterial smooth muscles
Hypertension
In smooth muscles, calcium influx from L-type calcium channels in cardiac and smooth muscle is responsible for normal resting tone and contractility.
Cardiac Muscle
Lower the tonicity of coronary arteries.
Calcium Channel Blockers
Calcium channel blockers affect ______.
Action Potential; SA and AV nodes depend on calcium.
Calcium channel blockers reduce ________ in all cardiac cells and reduce cardiac ________.
ECC; Contractility
Calcium channel blockers reduce ______ by the heart.
Oxygen demand
Inhibit angiotensin-converting enzyme
ACE Inhibitors
*Block the conversion of angiotensin I to angiotensin II (angiotensin II is a potent vasoconstrictor).
Responsible for converting angiotensin I to angiotensin II.
Angiotensin-converting enzyme
A powerful vasoconstrictor
Angiotensin II
Block the receptors, thereby preventing angiotensin II from hooking onto these receptors
Angiotensin receptor blockers (ARBs)
- Used in the treatment of hypertension and congestive heart failure
- Relax vasculature, decrease blood volume, and decrease oxygen demand from the heart
- ACE prevents the conversion of angiotensin I into angiotensin II – the latter protein being responsible for blood pressure raising effects.
Angiotensin receptor blockers (ARBs)
