Lecture 3 Muscarinic Agonists Flashcards
Diabetic neuropathy mechanisms:
- ____ insult to nerve fibers
- _____ insufficiency
- _____ damage
- _____ ____ factor defeciency
metabolic
neurovascular
auto-immune
neurohumoral growth
Most important form of autonomic neuropathy? Increased risk of what?
cardiovascular;
“silent” ischemia aka painless ischemia
_____ from excess alcohol is toxic to nerves. Chronic alcohol use can also cause _____, which further preciptates autonomic dysfunction
acetaldehyde;
chronic liver disease
Advanced chronic liver disease patients will suffer from peripheral _____ ____ and increased plasma levels of ____. Patients often present with _____ ____
arterial vasodilation;
catecholamines;
orthostatic hypotension
botulinim toxin interacts with ____ proteins, preventing vesicle ____ release
SNARE; ACh
Graves disease: increased secretion of T3 and T4 causes an increase in ______ _____ expression. This can cause ______ heartbeat and _____cardia. Treatment should be _____, which prevents conversion of T4–>T3. Muscarinic agonists are contra-indicated due to increased risk of _____
beta adrenergic;
irregular, tachy;
beta blockers;
Atrial fib
Reduced body weight/stress causes ______ to be released by the adrenal gland. This inhibits formation of ___. This causes a ____ of Sympathetic activation and a _____ of parasympathetic activation
glucocorticoids; T3
decrease; increase
Elevated body weight causes an ____ in T3 and a ____ in sympathetic nervous system activation
increase; increase
desensitization of the adrenergic system can exacerbate ______thyroidism. Sensitization of the adrenergic system can exacerbate _____thyroidism
hypo, hyper
treatment of hypothyroidism is typically with ____, rather than symptomatic treatment with ____ agonists.
hormones;
muscarinic
why isn’t clinical use of muscarine recommended?
can cross the BBB and cause convulsions
ACh, carbachol, methacholine, and bethanechol have a _____ ammonium and thus have limited ____ distribution and ___ absorption
quarternary;
CNS, GI
typically given GI or IM
What 2 muscarinic agonists are hydrolyzed quickly by AchE? Which three can bind to nicotinic receptors as well?
Ach, methacholine;
Ach, carbachol, methacholine
Hydrolysis by AchE means the drug is ___ acting. nAchR activity increases the risk of fatal _____ weakness
short;
muscle
____ is used to diagnose bronchial hyperactivity and COPD due to its short action. Patients with COPD will show signs of respiaratory insufficiency at a ____ dose than healthy individuals
methacholine;
lower
____ angle glaucoma is due a clogged or obstructed canal of schlemm. This is a ____ progressing disease
open; slowly
___ angle glaucoma is due to drainage blocked by the iris muscles or lens, blocking the trabecular meshwork This is a ____ progressing disease
closed/narrow; rapidly
MEDICAL EMERGENCY
Open angle treatment: M3 muscarinic agonist mechanism of action:
Narrow angle treatment: M3 muscarinic agonist mechanism of action:
(what is the normal treatment?)
Open: stretch trabecular meshwork by contracting ciliary body–>reduce clogging
Closed: contracts sphincter muscles->
usually laser iridotomy
muscarinic agonists used for treatment of glaucoma:
____ is shorter acting, is a partial agonist, = ____ side effects
_____ has a longer duration
which can cross the BBB?
pilocarpine; less
carbachol
pilocarpine can cross BBB (seizure risk)
Uses of bethanechol: 2
It is ____ selective
urinary retention, post-operative illeus
muscarinic
2 drugs used for xerostomia (ie Sjogren’s or head/neck irradiation)
cevimeline, pilocarpine
2 NAChR agonists used for smoking cessation:
which is a full and which is a partial agonist?
nicotine (full), varenicline (partial–>blocks nicotine from binding)
contraindication of nicotine? due to increased ____ and ____
cardiovascular disease;
blood pressure, heart rate