Autonomic Nervous System Flashcards
Which of the following neurotransmitters are released
by second order (post-synaptic) nerve terminals of the
Sympathetic nervous system?
A. Dopamine B. Norepinephrine C. Epinephrine D. Acetylcholine E. All of the above
E. All of the above
**Acetylcholine on sweat glands
**Dopamine on kidneys
Which kind of G receptor do M2 and M4 receptors activate?
Gi
-decreases cAMP and opens K+ channels
What kind of G receptor do M1, 3, and 5 receptors activate?
Gq
-increases IP3 thus intracellular Ca
What kind of G receptor do alpha-2 receptors activate?
Gi
-Decreases cAMP and opens K+ channels
What kind of G receptor do alpha-1 receptors activate?
Gq
-increases IP3 and thus intracellular Ca2+
What kind of G receptor do beta-1, 2, and 3 receptors activate?
Gs
-increases cAMP, opening Ca2+ channels
What is the exception to the rule that ANS innervation is dual (both symp and parasymp)?
-skin and blood vessels only receive sympathetic innervation
What is happening in the autonomic ganglia?
A. Acetylcholine released; binds & Opens nicotinic ion channels
B. Acetylcholine released; activates G protein-coupled receptors
C. Norepinephrine released; binds & opens nicotinic ion channels
D. Acetylcholine released; binds & inhibits nicotinic ion channels
A. Acetylcholine released; binds & Opens nicotinic ion channels
Which ANS receptors in the airway constrict the airway?
- M3
- H1 (histamine)
Which ANS receptors in the airway dilate the airway?
- B2
- Nitric Oxide
Which receptors in the SA node will decrease HR when activated?
-M2
Which receptors in the SA node will increase HR when activated?
-B1
Which receptors in the myocardium will increase contractility when activated?
-B1 and B2
What receptors will dilate blood vessels when activated?
- B2
- Nitric Oxide
What receptors will constrict blood vessels when activated?
a1
Which cells and receptors in pancreas will increase glucagon levels upon stimulation?
- Alpha cells
- B2 receptors
Which cells and receptors in pancreas will decrease insulin release upon stimulation?
- Beta cells
- a2 receptors
What receptors will cause the liver to release glucose when activated?
B2
Glucagon receptor
In a person who is jogging,
one is trying to keep glucose
and fatty acid levels high.
Which of the following hormone
levels will decrease under
these conditions?
A. Epinephrine B. Norepinephrine C. Glucagon D. Insulin E. Growth hormone
D. Insulin
Describe Horner’s Syndrome?
- occurs from lesion along sympathetic chain innervating the eye
- only one side (chance of both trunks being severed is slim)
How does signal termination occur at an adrenergic nerve terminal?
-80-90% reuptake
How does histamine lead to fluid exiting capillaries?
- H2 receptors on arteriole dilates vessel
- Hi receptors in endothelial cells of capillaries constricts, causing gaps between cells for fluid to exit
- H1 receptors on venule contract smooth muscle, constricting vessel
What do B1 receptors in the pituitary do when activated?
-cause increased ADH secretion, thus water reabsorption
Which of the following will improve renal blood flow?
A. Dopamine B. Angiotensin II C. Prostaglandin E2 D. Norepinephrine E. Dopamine and Prostaglandin E2
E. Dopamine and Prostaglandin E2
Adrenergic nervous system is generally mediated by
Norepinephrine and Epinephrine
Name an EXCEPTION to this general rule.
A. Temperature control by acetylcholine B. Temperature control by angiotensin II C. ADH release by acetylcholine D. Aldosterone release by acetylcholine E. Sweat glands by acetylcholine
A. Temperature control by acetylcholine
&
E. Sweat glands by acetylcholine
What is the effect of albuterol (a Beta 2 agonist)
on blood glucose levels?
A. Increase
B. Decrease
A. Increase
Which of the following constricts mostly
efferent arterioles resulting in increased GFR?
A. Dopamine B. Angiotensin II C. Prostaglandin E2 D. Norepinephrine E. Atrial Natriuretic Factor
B. Angiotensin II
You prescribe Terazosin (Hytrin), an alpha-1 blocker to
an elderly male for an enlarged prostate.
(Remember BPH? Benign Prostatic Hypertrophy)).
What is the effect of an alpha-1 blocker on blood pressure?
A. Increase
B. Decrease
B. Decrease
On what type of neurons do N1/Nm and N2/Nn receptors present?
N1 = Neuromuscular
N2 = Ganglionic & neuronal
What is Bethanechol used to treat?
Urinary Retention
cholinergic agonist
What is Pilocarpine used to treat?
Acute Glaucoma
Dry mouth
What are the general adverse effects to cholinergic drugs?
- Bradycardia, decreased CO, Hypotension
- Bronchoconstriction
- Nausea, Vomiting, diarrhea
- Sweating, salivation, urinary urgancy
**DUMB BELSS
What is Neostigmine used to treat?
Myasthenia Gravis
What Donepezil used to treat?
Alzheimer’s
Which of the following drugs helps Alzheimer’s patients?
A. Scopalamine B. Bethanechol C. Neostigmine D. Donepezil E. Atropine F. Edrophonium
D. Donepezil
Which of the following drugs is a reversible inhibitor?
- Aspirin
- Clopidogrel (Plavix)
- Omeprazole (Prilosec)
- Simvastatin
- Echothiophate
- Sarin
- Simvastatin
What is the overall effect of epinephrine on blood glucose?
Will increase blood glucose.
-by decreasing insulin release and increasing glucagon release
What do kidneys secrete when their B1 receptors are activated?
Renin, activates RAAAS pathway
What does Atropine Do?
Treats Organophosphate poisoning.
-Muscarinic blocker
What does pralidoxime (PAM) do?
- treats insecticide (nerve gass) poisoning
- recovers ACE activity if given early
Where is the site of action of ganglionic blockers?
- nicotinic receptor in autonomic ganglia
- includes adrenal medulla
Where is the site of action of antimuscarinic (muscarinic blocker) drugs?
-muscarinic receptors of post-ganglionic neurons in parasympathetic NS
Where is the site of action of neuro-muscular blockers?
- neuromuscular junction
- affect muscle contraction in somatic NS
What is mydriasis?
dilation of the pupils
What are the effects of antimuscarinics on the respiratory system?
- bronchodilation
- decreased secretions
What type of drugs are atropine, scopalamine, glycopyrollate, and ipratropium?
- specific anti-muscarinic drugs
* work at synapse between postganglionic PNS neuron and organ
What is Ipratropium used for?
-produce bronchial dilation in COPD
What is Glycopyrollate used for?
-used preoperatively to reduce secretions
What is Atropine used for?
- can be used preoperatively to reduce secretions
- bradycardia
- antidote for cholinergic drugs
- antidote for nerve gas
What is scopalamine used for?
- can be used preoperatively to reduce secretions
- Prevent motion sickness
What does 2-PAM do?
- regenerates ACh esterases
- used for nerve gas poisoining
**doesn’t enter CNS
Does 2-PAM enter the CNS?
No
Does Atropine enter the CNS?
-yes
Where are the majority of cholinergic receptors located in the airway?
-large central airways
Where are the majority of adrenergic receptors located in the airway?
-small peripheral airways
What is Theophyline used for? What receptor does it use?
- asthma and COPD
- Adenosine receptor
**LOW therapeutic index
What is the mechanism of action of Ganglionic blockers?
-interfere with the postsynaptic action of ACh at the Nn receptor of autonomic ganglia
What are the general uses of ganglionic blockers?
-treat hypertension in an emergency
**very limited clinical use
What type of drugs are mecamylamine and trimethaphan?
ganglionic blockers
What is the mechanism of action of depolarizing NMJ blockers?
- binds to Nm receptor, OPENS THE CHANNEL, depolarizes the end-plate, then gets stuck
- membrane repolarizes, but receptor is desensitized to the effect of ACh
What are the uses of depolarizing NMJ blockers?
-to produce skeletal muscle relaxation
What drug is a depolarizing NMJ blocker?
-Succinylcholine
What is succinylcholine used for?
-relax muscles during surgery
depolarizing NMJ blocker
What is the mechanism of action of Nondepolarizing neuromuscular antagonists?
-bind to Nm receptor, but do not open the channel
What are the uses of nondepolarizing NMJ blockers?
-produce skeletal muscle relaxation
What kind of drugs are d-tuboCURarine, panCURonium, atraCURium, and gallamine?
-nondepolarizing NMJ blockers
How would you bring a patient off of one of the nondepolarizing blockers? Why?
- Administer a cholinesterase inhibitor along with a muscarinic antagonist.
- include a muscarinic antagonist to protect heart from excess acetycholine (remember location of muscarinic vs nicotinic receptors)
What is the mechanism of malignant hyperthermia?
- triggered by halothane or succinylcholine
- agents trigger a release of calcium from SR
- increased myoplasmic Ca activates myosin ATPase and generates heat
What is Dantrolene used for? How does it work?
- treats malignant hyperthermia
- blocks Ca release from SR
How does Botox work?
-blocks vesicular release of ACh
What is botox used for besides cosmetic effects?
- focal dystonia (local movement disorders)
- Strabismus (eyes not aligned
- Cervical dystonia (head tilt)
- chronic migraines
How do you treat an overdose of atropine?
- treat symptomatically
- provide cholinesterase inhibitor
- blankets and diazepam for seizure control
How is an overdose of anti-cholinergic drugs treated?
In addition to support therapy, which of the following drugs
In low doses is helpful?
A. Scopalamine B. Echothiophate C. Neostigmine D. Donepezil E. Physostigmine
E. Physostigmine
**Neostigmine only works in periphery. Physo works centrally AND peripherally
Which one of these is a depolarizing neuromuscular junction blocker?
A. Atropine B. Bethanechol C. Succinylcholine D. Curare E. Gallamine
C. Succinylcholine
Which one of these drugs is a commonly used bronchodilator?
A. Atropine B. Scopolamine C. Ipratropium D. Theophylline E. Diphenhydramine
C. Ipratropium
What drug treats malignant hyperthermia?
-Dantrolene
Why isn’t atropine used as a bronchodilator?
it enters the CNS
Why isn’t scopalamine used as a bronchodilator?
-it enters the CNS