Sympatholytics in Control of Blood Pressure Flashcards
(36 cards)
What are the two component of the Peripheral Nervous System?
Autonomic Nervous System [What your body does for you]
Somatic Nervous System [What your able to physically do]
What are the two components of the Autonomic Nervous System?
Sympathetic [Fight or Flight]
Parasympathetic [Rest and Digest]
What is the first line medication for HTN?
NOT sympatholytic drugs
-CCB, ACE-I, ARBs, and Diuretics are considered the first line
Should sympatholytics be used in pregnany?
NO, they are contraindicated in pregnancy; BUT you can use Methyldopa + Labetolol just fine?
What does the Baroreceptor do… again?
The stretch receptors within the aortic arch and the carotid sinus. When it stretches the a signal is sent to the medulla. Then a signal is sent from the medulla back to the target organs.
What will increase the baroreceptor response?
Drugs that reduce and increase the reflex tachycardia
What is the MOA of the Alpha-1 Antagonists?
Normally A1 receptors are going to release NE causing the Vasoconstriction.
-A1 Antagonists are going to block the release of NE, causing vasodilation which will decrease VR & CO = decrease in BP
-also helps relax the sphincter tone at the bladder, increasing urination during BPH
What are the Alpha-1 Antagonists?
The “-zosins”
-Prazosin, Terazosin, Doxazosin, Tamsulosin…
What are the side effects of The “-zosins”?
Orthostatic Hypertension [1st time], Tachycardia, Dizziness
What is Clonidines MOA?
Baroreceptor like: There is an increase of signal down the Vagus Nerve into the medulla, that signal will then travel back down the efferent nerve to the target organ, decreaseing VR, HR, CO = DECREASE in BP
What do the Alpha 2 Agonist do within the body?
With the agonism, there is a blockage of Nor-epi, causing inhibition of the Alpha and Beta receptors, causing a decrease in VR/CO = DECREASE in BP
What are the Alpha 2 Agonist?
Methyldopa, Clonidine
What is important about Methyldopa?
-One of a few medications that can be used during Pregnancy.
-Prodrug
What are the side effects of Clonidine?
Dry mouth, Sedation, Rebound Hypertension
What is a Non-selective Alpha Blocker?
An Alpha Blocker that has the ability to block both Alpha 1 and Alpha 2
How do the Non-selective Alpha Blockers work?
They are not as selective for Alpha 1; so they will have the ability to pass through the BBB binding to the Alpha 2 receptors there, causing the inhibition of the Negative Feedback Loop = INCREASE REFLEX TACHYCARDIA
What are the Non-selective Alpha Blockers?
Phentolamine, Phenoxybenzamine
What is important about Phentolamine?
-it is reversible
-has a very short duration
-binds to the ACTIVE site [directly inhibits Nor-epi & Epi]
What is important about Phenoxybenzamine?
-it is irreversible [receptor as nucleophile??]
-has a long duration
-binds to the ALLOSTERIC site [indirectly inhibits Nor-epi & Epi]
What do the First Generation Beta-Blockers do?
They are a Non-Selective Beta Blockers [B1 & B2]; blocking the effects of Epi = DECREASE in CO & VR causing a DECREASE in BP
The primary use of First Generation Beta-Blockers?
angina, cardiac arrhythmia, reduce tremors
What are the First Generation Beta-Blockers?
The “-olol” meds
-Propranolol, Pindolol, Acebutolol…
What is the importance of Propranolol?
-The 1st First Generation Beta-Blocker
-Unselective: Blocks both B1 & B2
-Will DECREASE BP by reducing Renin [B1]
What are the side effects of Propranolol?
Bronchospasm [B2], Bradycardia [B1], Rebound Tachycardia, Hypertension…