Chapter 2: Cholinergic Pharmacology Flashcards
MOA of hemocholinum.
blocks uptake of choline
MOA of botulinum toxin.
cleaves SNARE proteins involved in exocytosis of ACh
Xerostomia definition and why is this caused? (what is defective)
dry mouth
salivary glands don’t produce enough saliva
M1 and M3 correspond with what receptor pathway?
(what coupled pathway or second messenger pathway)
Gq coupled
increase phosphliase C > increase IP3, DAG, Ca2+
M2 goes through what coupled receptor pathway?
(what second messenger pathway in other words)
Gi coupled
dec. adenylyl cyclase > dec cAMP
Nn and Nm go through what G coupled receptor pathway?
trick question
no 2nd messengers
activation through opening of Na/K channels
Stem to remember muscarinic agonist
“chol”
Clinical use of bethanechol.
Rx: ileus (postop); urinary retention
Use of methacholine.
Dx: bronchial hyperactivity (challenge test)
Use of pilocarpine, cevimeline.
Rx: xerostomia, glaucoma (pilocarpine)
Stem to help you remember indirect acting cholinomimetics.
stigmine
Clinical use for edrophonium
Dx myasthenia gravis
Benefits to edrophonium typically being used as a diagnostic tool?
short acting
Clinical use of physostigmine?
Rx: glaucoma; antidote in atropine overdose
Why can physostigmine be used for atropine overdose? (characteristics that make it suitable)
tertiary amine
very lipid soluble
(readily enters CNS)
Neostigmine and pyridostigmine can be used for what?
ileus, urinary retention, myasthenia gravis, reversal of non depolarizing NM blockers
Characteristics of neostigmine and pyridostigmine that do not make it suitable for atropine overdose?
Quaternary amine so cannot enter CNS
Donepezil clinical use.
Rx - Alzheimers
Rivastigmine clinical use.
RX - Alzheimers
Organophosphate use. (Name some)
used as insecticides (malathion, parathion) and sarin ( nerve gas)
Some properties of donepezil and rivastigmine that make them ideal for treating Alzeihmers?
lipid- solubility
Way to remember difference between physostigmine and pyridostigmine.
“pyro burns down”
pyro below CNS and physo above so good for atropine overdose
DUMBBEELSS acronym use?
clues to tell if someone has AChE inhibitor poisoning
Use the proper acronym to be able to tell if someone has AChE inhibitor poisoning.
DUMBBEELSS
diarrhea
urination
miosis
bradycardia
bronchoconstriction
emesis
excitation (CNS/muscle)
lacrimation
salivation
sweating
What is the most deadly S/E of AChE inhibitor poisoning?
paralysis of diaphragm
Use of pralidoxime.
Reversal of irreversible AChE inhibitors
What is the prototype of the muscarinic receptor antagonist class?
atropine
What is the characteristic of atropine that makes it a good antidote for AChE inhibitors?
tertiary amine; readily enters CNS
What plant atropine derived from?
atropa belladonna; Jimsonweed
Muscarinic antagonist effects on eyes?
mydriasis and cycloplegia
Pharamacologic effects of muscarinic receptor anatagonists? (name 2 or 3)
- decrease secretions (salivary, bronchiolar, sweat)
- mydriasis and cyclopegia
- hyperthermia (with resulting vasodilation)
- tachycardia
- sedation
- urinary retention and constipation
- Behavioral: excitation and hallucinations
Name some classes of drugs with antimuscarinic properties.
antihistamine (particularly the 1st generation)
tricyclic antidepressants
antipsychotics
quinidine
amantadine
meperidine
Antidote for antimuscarinic drugs?
physostigmine
Clinical use of atropine.
antispasmodic, antisecretory, management of AChE inhibitor OD, antidiarrheal, ophthalmology (but long action)
Clinical use of tropicamide.
ophthalmology (topical)
Clinical use of ipratropium, tiotropium. Also name some important properties to remember about these drugs. (Can they enter CNS) (How do they effect mucus viscosity)
asthma and COPD (inhalation) - no CNS entry, no change in mucous viscosity
Stem to remember M blockers?
“trop”
Scopolamine clinical use. Also S/E.
motion sickness
causes sedation and short-term memory block
Benztropine and trihexyphenidyl clinical use.
lipid-soluble (CNS entry) used in Parkinson-ism and in acute extrapyramidal symptoms induced by antipsychotics
Clinical use of oxybutinin.
used in overactive bladder (urge incontinence
What makes tropicamide a more useful drug in eye exams than atropine.
causes less sustained dilation of pupils because of its short half-life
What are ganglion blockers also typically named?
nicotinic receptor antagonist
What are 2 ganglion blockers not used today but that this chapter covered?
hexamethonium. and mecamylamine
Ganglion blockers have what effect that can be useful?
they block reflexes
Which receptors are stimulated for direct action on HR?
M2 and B1
What receptors are stimulated for indirect effect on HR causing reflex Brady or tachy?
a1 (vasoconstriction) and B2 (vasodilation)
