ANS Flashcards
Name receptors that work through Gq signaling.
What is the second messenger?
M1, M3, alpha-1
Activation PLC –> increase IP3/DAG –> increased Calcium
Name receptors that work through Gi signaling.
What is the second messenger?
M2, alpha-2
Inhibition of AC –> decreases cAMP
Name receptors that work through Gs signaling.
What is the second messenger?
beta 1, 2, 3
Activation AC –> increase cAMP
Name the anatomical divisions of ANS.
Parasympathetic – Thoracolumbar (long pre & short post)
Sympathetic –Craniosacral (short pre & long post)
Quick way to remember signaling used…
QIQ – M1, M2, M3
QISS – alpha1, alpha2, beta1, beta2
Nicotinic receptors work through?
Ion channels
What are the effects of ACh in body?
D - diarrhea U - urination M - myosis (contraction of sphincter pupillae) B - bronchospasm B - bradycardia E L - lacrimation S - salivation/sweating
What are the effects of NE in body?
Opposite of DUMBBELS.
Constipation, urinary retention, mydriasis, bronchodilation, tachycardia, decreased lacrimation / sweating / salivation.
What are the effects of ACh and NE on Ciliary muscle?
ACh – cyclospasm (contraction of muscle, accommodation for NEAR vision) and increased AH drainage
NE - alpha 2 (decreases AH production)
beta 2 (increases AH production)
Where are these receptors located? M1 M2 M3 alpha 1, 2 beta 1, 2 Nn, Nm D1, D2
M1 - CNS M2 - Heart M3 - everywhere else (smooth muscle, sphincters, glands, ciliary muscle, corpora cavernosum). alpha1 - BV, radial muscle iris, smooth muscle, sex organs alpha2 - presynaptic neurons beta1 - Heart beta2 - smooth muscle, BV Nn - neurons Nm - skeletal muscle D1 - renal BV D2 - CNS, presynaptic neurons
ACh has no clinical significance but stimulate _____ to release ____ and cause ____.
Stimulates endothelium release NO (endothelial-derived relaxing factor) VASODILATION
Methacholine, a direct cholinergic agonist used to diagnose ___.
Bronchial Asthma
Bethenicol acts on _____.
Used to treat ___ & ____.
Muscarinic R > Nicotinic R
Paralytic ileus and Urinary retention
Pilocarpine only acts on ____ receptors.
Used in conditions like ___, ___.
Muscarinic R only
Glaucoma (stimulates drainage of AH)
Sjögren Syndrome (stimulates gland secretions)
Myasthenia Gravis, autoimmune disorder characterized by Ab destruction of Nm receptors.
The drug ____ is used to diagnose type of MG.
Edrophonium (Tension test)
Short acting drug given IV. If patient gets better (Dx Myasthenia crisis), if patient gets worse (Dx Cholinergic crisis).
Myasthenia Gravis is treated short term with _____, and long term with _____.
Neostigmine (short acting, acute/hospital symptoms, IV)
Pyridostigmine (long acting, orally).
Name 3 drugs used to treat Alzheimer’s disease.
Tacrine (discontinued), Rivastigmine, Donezapil.
Are highly lipid-soluble and cerebroselective
Name a indirect cholinergic agonist used to treat Glaucoma.
Physostigmine (lipid soluble). Causes increased drainage of AH.
Irreversible cholinergic agonists are mostly OP. Name 3.
Name MOA of OP.
Malathion, Parathion, Sarin.
Phosphorylate AChE –> irreversible inhibition
Name symptoms of OP poisoning.
Myosis, diarrhea, vomiting, sweating, blurred vision, bradycardia, bronchial constriction, urination…basically effects of excess ACh.
Name drugs used to treat OP poisoning.
1 ATROPINE (Muscarinic R antagonist): given until patient gets mydriasis, tachycardia and dry mouth.
PRALIDOXIME: AChE reactivate, hydrolyzes drug bound to enzyme. Must be given before Aging of bond occurs.
Atropine is a _____.
Name 3 uses for it.
Muscarinic R blocker.
- OP poisoning
- Heart block
- Bradycardia
Name a Muscarinic R blocker used for Refraction error testing & mydriasis for Fundoycopic examination.
Tropic amine (short acting atropine) Causes: mydriasis, cyclopegia (paralysis of ciliary muscle, loss accommodation, can't see near objects).
Refraction error testing requires dilatation of pupil (mydriasis) for visualization of retina. Name two drugs used.
Atropine, Tropicamine (muscarinic R blockers)
Phenylephrine for elderly (alpha-agonist).
Name DOC for treatment of Drug induced Parkinson’s disease.
Benztropine (M R blocker)
Name Muscarinic R blocker used to treat COPD/Bronchial Asthma.
Ipratropium bromide
Name Muscarinic R blocker used to treat Peptic Ulcers.
Pirenzepine (stops acid release by Parietal cells)
_____ is used to treat Motion sickness by acting in CTZ vomiting center in 4th ventricle wall.
Scopolamine
_____ causes relaxation of smooth muscle, and used to treat GI spasms, Spasmodic abdominal pains, Menstrual pains.
Dicyclomine
Name 2 drugs used as muscle relaxants, that work on Nm receptors.
Tubocurarine
Succinylcholine
Name 2 drugs that block Nn receptors.
Hexamethonium, Mecamylamine
No longer used due to non-specific effects, high toxicity and hypotension
Name 3 alpha/beta agonists.
Epinephrine, NE, Pseudoepinephrine.
___ preferentially binds beta > alpha receptors and has a biphasic curve on high dose.
Epinephrine
High dose Epinephrine causes ____ SBP, ____DBP, ____MAP, and ____ PP.
increase SBP
decrease DBP
increase MAP
Increase PP
Low dose Epinephrine causes _____ because ____.
vasodilation (decrease DBP)
preferential binding of beta2 over alpha1 in BV
Name uses of Epinephrine.
Acute hypersensitivities
Retard absorption local anesthetics (alpha1 action)
Cardiac arrest (alpha1 action)
What drug has no beta2 action and causes Reflex Bradycardia by increasing BP.
Norepinephrine
Increases BP, sensed by Baroreceptors, decreases HR.
What are the effects on HR, SBP, DBP and PP by NE.
increase SBP (a1) increase SBP (a1) increase PP decrease HR (baroreceptor reflex)
___ is an alpha1 selective agonist used for___ (4 uses).
Phenylephrine
- Postural hypotension
- Nasal decongestion
- Mydriasis in elderly
- Local vasoconstrictor
Why is phenylephrine used in elderly to cause Mydriasis instead of Atropine?
Atropine blocks Muscarinic R causing constriction of ciliary muscle and increasing IOP (decreasing outflow AH).
Phenylephrine binds alpha1 R o dilator pupillae.
Alpha2 selective agonist can be used in HTN. ____ #2 DOC in HTN while _____ is DOC in HTN in pregnant woman.
Clonidine (also used for withdrawal of alcohol/tobacco/opioids).
Alpha-methyldopa
Name an alpha2 selective agonist used to treat Glaucoma and its MOA.
Apraclonidine (binds alpha2 causing decrease AH production).
Name alpha2 agonist used to treat Spinal cord Spasticity.
Tizanidine
Isoprotenol is an beta1/beta2 agonist that causes ___ and ____.
increase HR (beta1) vasodilation and decrease DBP (beta2)
Name a physiological consequence of Isoprotenol administration.
Reflex tachycardia.
Vasodilation decreases BP, causes increase HR (binds beta1 R).
Name changes in DBP, SBP, HR and MAP by Isoprotenol.
decreases DBP
no change SBP
decrease MAP
increase HR
Isoprotenol used to treat ___and ___.
Heart block
Bradycardia
Beta1 selective agonist ____, used to treat Cardiac Failure, or Cariogenic shock in people with severely decreased LV function.
Dobutamine
Beta2 selective agonists like ___/____ used to treat Bronchial Asthma.
Albuterol
Salmetrol
Name 4 side-effects of beta2 agonist usage.
- tremors
- tachycardia, palpitations, flushing skin
- HYPOKALEMIA
- down regulation beta R (long-term usage)
Dopamine has dual effect, high dose binds___ and causes ___, while low dose binds ___ and causes ___.
D1 R –> vasodilation
alpha/beta R –> increased SBP, increase PP, NE release from nerve terminals
Name effects of these Indirect acting adrenergic drugs.
- Amphetamines, Dextroamphetamine, Methylphenidate
- Tyramine
- Cocaine
- stimulate release monoamines (E/NE/DA) and blocks their reuptake
- False transmission, taken up when converted to Octopamine and increases NE concentration.
- Blocks catecholamine reuptake, stimulates pleasure centers of brain
Explains Cheese Effect.
Eating foods high in Tyramine while on MAO inhibitors leads to increase NE leading to Hypertensive crisis.
Alpha blockers cause vasodilation leading to ___ and ____ in HR as a reflex.
hypotension increase HR (blocks alpha2 R --> NE release not inhibited)
_____ makes covalent bonds with receptors, making it an Irreversible alpha blocker.
What is the effect seen in DRC?
Phenoxybenzamine
Decrease in height (decreased efficacy).
Name two alpha blockers used in Pheochromocytoma.
Phenoxybenzamine
Phentolamine
Name 2 drugs that cause Reflex tachycardia.
- NE
2. alpha blockers
___ is used to treat BPH by inhibiting _____; prevents contraction of muscles and allows urinary outflow.
Tamsulosin
alpha-1-a
___ is used to treat Essential HTN, and HTN due to clonidine or Cheese Effect, PVD, and Raynaud’s disease.
Prazosin
Name some effects of beta-blockers.
decrease HR decrease O2 demand decrease CO and BP bronchoconstriction decrease AH production by ciliary epithelium decrease Renin release Blocks catecholamine induced tremors
Name some Cardio-selective beta1 blockers.
Atenolol Betaxolol Esmolol Acebutolol Metoprolol
A-BEAM (names A-M)
Name side-effects of beta-blockers.
Bradycardia
Bronchospasm
Masks signs of hypoglycemia (tachycardia, tremor, anxiety, sweating)
up-regulation of beta-R (if stop suddenly)
Name beta-blocker used in:
- Migraines
- Glaucoma
- Arrhythmias
- Propranolol
- Timolol (decreases AH production)
- Sotolol (increases AVN refractory period by blocking K+ channels)
___ is an a1/b1/b2 blocker used for CCF along with ACE inhibitors.
Carvedilol
____ is an a1 R antagonist and a b1/b2 partial agonist used in Emergency Hypertensive situations by ____.
Labetalol
decreases TPR (minimal changes to CO and HR)
___ is an Indirect antiadrenergic by blocking _____ (enzyme in catecholamine biosynthesis). Can be used in Pheochromocytomas.
Metyrosine
Tyrosine Hydroxylase
