Drugs acting on the Autonomic Nervous System Flashcards
Rotation 1 - week 2
what do adrenergic receptors respond to?
norepinephrine and epinephrine
What do cholinergic receptor sites respond to?
Acetylcholine
Monoamine oxidase is an enzyme that breaks down ____, ______ and ______ to make them inactive.
norepinephrine
dopamine
serotonin
what do sympathomimetic drugs do?
these are drugs that MIMIC the actions of of the sympathetic nervous system
What is the sympathetic nervous systems “job”?
protect the body in times of stress or danger; “fight or flight”
What kind of receptors are in the sympathetic nervous system?
Alpha + Beta
what receptors do beta agonists specifically stimulate in the SNS?
Beta Receptors
What do beta - adrenergic blocking agents do within the SNS?
block the beta receptors
The enzyme acetylcholinesterase, is responsible for breaking down what?
acetylcholine
what do parasympathomimetic drugs do?
and what is being mimicked?
these mimic the effects of the PNS; acetylcholine
What is Myasthenia Gravis?
an autoimmune disease characterized by antibodies to cholinergic receptors; causing muscle weakness
what do anticholinergic drugs do?
oppose the effects of acetylcholine
what is mydriasis?
this is when the muscles around the pupil relax, which causes pupil dilation
What describes parasympatholytic?
this is a drug that’s blocking or reducing the parasympathetic effects
What is Alpha 1 do when stimulated?
peripheral vasoconstriction
What does Beta 1 do when stimulated?
HR, contractility, blood pressure and blood volume all increase + dilate the pupils
What does Alpha 2 do when stimulated?
this is the brain keeping everything “in check” - to prevent a too exaggerated of a response
What do Beta 2 receptors do when stimulated?
this is the relaxation of smooth muscle
1.airway
2.GI tract
3.bladder
4.vessels
what is the parasympathetic nervous system responsible for?
the “rest and digest” of the body; maintaining regulatory tasks in the body
What are the 2 receptors in the parasympathetic nervous system ?
muscarinic and nicotinic
What are the actions of cholinergic drugs?
-enhance digestion
-promote urination
-slow heart rate
-increase secretions
-constrict pupils
Bethanechol is indicated for acute post op/ post partum urinary retention or neurogenic bladder atony w/ retention, what is the action of this drug?
this drug increases tone and promotes emptying of the bladder
Bethanechol is a ________. its a parasympathomimetic that mimics acetylcholine.
cholinergic agonist
indirect acting cholinergic agonist is also mimicking acetylcholine by inhibiting what enzyme?
acetylcholinesterase
What indirect acting cholinergic agonist is used to treat myasthenia gravis, by inhibiting acetylcholinesterase which increases Ach?
Pyridostigmine
Anticholinergics are Para-sympatholytic which means they are _________ the action of Ach. Which is inhibiting he __________, therefore promoting the “fight or flight” response in the ___________.
-blocking
-parasympathetic nervous system
-sympathetic nervous system
Atropine is an Anticholinergic that blocks muscarinic receptor sites, what are some of its uses?
-decrease secretions prior to surgery
-Parkinson’s
-restore cardiac rate post vagal stimulation
-relief of bradycardia
what is happening in the body when the SNS is promoted, when anticholinergic drugs are taken? (5)
-decreased secretions
-smooth muscle relaxation
-increased heart rate
-pupils dilate
-GI motility slows
What are the 4 main side effects of anticholinergics?
-dry eyes + blurry vision
-urinary retention
-dry mouth + less sweating
-constipation
which drug is used to correct hemodynamic imbalances in shock, vasodilates, maintains perfusion + stimulates the sympathetic response?
dopamine
DOPAMINE, ephedrine, dobutamine, epinephrine, norepinephrine + pseudoephedrine are all alpha + beta adrenergic ____________.
agonists
agonist is to sympathomimetic/parasympathomimetic as antagonist is to ____________/____________.
sympatholytic/para-sympatholytic
Phenylephrine is an alpha selective adrenergic agonist, used to ____ ____ _____ by causing vasoconstriction.
raise blood pressure
__________ is a beta selective adrenergic agonist used to treat low cardiac output and prevent bronchospasm under anesthesia. This drug is going to produce an ______ heartrate, ________ + vasodilate.
-isoproterenol
-increased
-bronchodilate
some adverse/ side effects of isoproterenol include:
-restlessness
-anxiety
-arrhythmia’s + tachycardia
-respiratory difficulty + cough
Beta 1 receptors relax the smooth muscle, Beta 2 receptors relax the bronchi, Beta 3 receptors relax the ___________, when stimulated.
bladder
Labetalol is used to treat hypertension by blocking ____ + _____ to lower BP without reflex tachycardia.
alpha + beta receptors
if phentolamine is blocking alpha receptors to cause vasodilation to lower BP + increase HR, what kinds of things will it be used to treat? (2)
-hypertension associated w/ pheochromocytoma
-prevent necrosis associated with extravasation
what medication is used to treat hypertension and BPH by reducing peripheral resistance?
doxazosin
true/ false? —- if a drug is an agonist that means that it stimulates the receptor, if a drug is an antagonist, that means it is blocking the receptor.
true
Renin is produced by the juxtaglomerular apparatus in the kidneys, to regulate blood pressure, fluid volume + sodium levels, if those receptors are blocked how is it going to effect blood pressure?
this is gong to bring blood pressure down.
which medication blocks beta adrenergic receptors in the heart and juxtaglomerular apparatus to bring down BP, prevent reinfarction after MI, prevent migraines + manage situational anxiety?
propranolol
when beta 1 is stimulated the smooth muscle of the heart is excited and the rate will be up, when Beta 1 is blocked this is decreasing excitability of the heart, cardiac output, and oxygen consumption. which medication is going to do this when used to treat angina, hypertension, MI and alcohol withdrawal?
Atenolol
