Cholinergic Drugs Flashcards
(115 cards)
1
Q
what is the main neurotransmitter of cholinergic drugs
A
acetylcholine
2
Q
what are the precursors of acetylcholine
A
acetyl coenzyme A
choline
3
Q
where is acetyl coenzyme A derived and synthesized from
A
derived: pyruvate
Synthesized: mitochondria
4
Q
True or False:
choline uptake is a rate limiting step
A
true
5
Q
what are the choline transport systems
A
high affinity transport system
synaptic vesicles by vesicular transporters
6
Q
what is the inhibitor of the high affinity transport system of choline
A
hemicholinium
7
Q
what is the inhibitor of the synaptic vesicles of ACh transport
A
vesamicol
8
Q
how is acetylcholine released
A
exocytosis
9
Q
what can inhibit the release of acetylcholine
A
botulinum toxins
10
Q
what can bind to the receptors of cholinergic nerve terminals to interupt the SNARE complex components
A
clostridium toxins
11
Q
which animal uses clostridium toxins to their advantage to kill
A
black widow spiders
12
Q
what enzyme is used to hydrolyze ACh
A
acetylcholinesterase
13
Q
what is the purpose of AChE
A
recycling of choline to increase ACh synthesis
14
Q
where is AChE synthesized
A
autonomic ganglia
neuromuscular motor endplates
visceral neuroeffector junctions
15
Q
what is the pseudo chE
A
butyrylcholinesterase
16
Q
where is butyrylcholinesterase synthesized
A
liver
17
Q
what is the purpose of butyrylcholinesterase
A
metabolism of certain drugs
18
Q
what occurs if there is an inhibition of AChE
A
accumulation of ACh in nerve terminal
19
Q
which receptors are involved with cholinergic receptors
A
nicotinic and muscarinic receptors
20
Q
what type of receptor are nicotinic receptors
A
ligand gated ion channel
21
Q
what is the main result of activating a nicotinic receptor
A
skeletal muscle contraction
22
Q
where are nicotinic receptors found
A
autonomic ganglion
adrenal medulla
CNS
23
Q
what type of receptors are muscarinic receptors
A
GPCR
24
Q
what are the responses of activating muscarinic receptors
A
excitatory
inhibitory
25
where are non-innervated muscarinic receptors found
vascular endothelium
26
which muscarinic receptor is normally found as non-innervated in blood vessels
M3
27
where are M1 receptors found
ganglia
secretory glands
28
where are M2 receptors found
myocardium
smooth muscle
29
where are M3 & M4 receptors found
smooth muscle and secretory glands
30
where are M5 receptors found
CNS
31
what is the most common muscarinic receptor
M5
32
which muscarinic receptors activate Gq proteins
M1
M3
M5
(odd receptors)
33
what type of responses are expected with the activation of M1, M3 or M5 receptors
excitatory
34
what muscarinic receptors are responsible for "relaxation"
M2
M4
35
which muscarinic receptors act on Gi protein
M2
M4
36
what is the result of M2 receptor activation of the heart muscle
decreased HR
decrease impulse conduction / contraction
37
what is the effect of activating M3 receptors of smooth muscle
increase in contraction (GI system)
38
what is the effect of activating M3 receptors of secretory glands
increased secretion
39
how do M3 receptors in vascular endothelium cause vasodilation
release of NO
40
what are the 2 types of cholinergic agonists
direct and indirect
41
how do indirect cholinergic agonists work
inhibit cholinesterase to cause accumulation of ACh
42
what are the direct acting agonists
carbachol
bethanechol
pilocarine
43
what are the reversible indirect cholinergic agonists
physostigmine
neostigmine
edrophonium
pyridostigmine
44
what is the irreversible indirect agonist
organophosphate
45
how do low doses of acetylcholine impact the cardio vascular system
rapid fall in pressure --> reflex tachycardia
muscarinic receptors of vascular endothelium are activated (M3 creates vasodilation)
46
what are the effects of high doses of acetylcholine
vasodilation --> decreased peripheral resistance and BP
slow HR (- chronotropic effect)
- inotropic effect
slow SA and AV node conduction
decreased cardiac output
47
how does acetylcholine impact smooth muscle
increase motility
increase GIT secretion
increase bronchial muscle contraction
increase urinary bladder contraction
48
how does acetylcholine effect exocrine glands
increase secretion
49
how does acetylcholine impact the eye
reduces intraocular pressure
contraction of iris muscle
50
what can be induced in the eye with acetylcholine
miosis
51
what are the choline ester direct-acting parasympathomimetic agonists
carbachol
bethanechol
52
what are the natural alkaloid direct-acting parasympathomimetic agonists
pilocarine
53
which direct-acting agonist is a very potent nicotinic and muscarinic agonist that is resistant to hydrolysis by AChE
carbachol
54
True or False:
Carbachol has a longer duration of action
true
55
what is the pathway of carbachol
stimulate autonomic ganglia = acetylcholine release
56
when should one administer carbachol
impaction colic in horses
glaucoma in dogs
rumen atony and impaction in cattle
57
when should you NOT administer carbachol
in cases of maybe solid impactions - can cause bowel ruptures
58
which direct-acting agonist is very potent and selective for muscarinic receptors and resistant to hydrolysis to AChE
bethanechol
59
when would you administer bethanechol
GI paralytic ileus
urinary retention associated with bladder muscle atony
60
what should you be aware of when thinking about using bethanechol
only use when there is no mechanical obstruction in GIT
61
what receptor does Pilocarine act on
M3
62
what is the effects of using M3
contraction of iris sphincter and ciliary muscle of the lens
63
what can pilocarine be used to treat
acute glaucoma
keratoconjunctivitis sicca
64
what are the therapeutic uses of parasympathomimetic
GI atony / impaction
urinary bladder muscle atony
glaucoma
65
how do reversible cholinesterase inhibitors work
inhibit ACh binding to AChE
66
how is physostigmine administered
orally
67
what is physostigmine used for
glaucoma
atropine toxicity
68
how is neostigmine administered
orally
69
what receptors does neostigmine work on
selective for nicotinic receptors at the Nm junction
70
when is neostigmine used (therapeutic)
myasthenia gravis
reverse neuromuscular blockade (non-depolarizing)
71
what type of inhibitor is edrophonium
competitive reversible inhibitor
72
when is edrophonium used (therapeutic)
anti-curare
myasthenia gravis
73
what is a longer acting drug used for myasthenia gravis
pridostigmine
74
what are the digestive pharmacologic effects of reversible cholinesterase inhibitors
increase GIT motility
increase frequency / strength of peristaltic waves
75
what should you be aware of (warnings) before using reversible cholinesterase inhibitors
intestinal spasm
colic
76
what are the ocular effects of using reversible cholinesterase inhibitors
pupillary constriction
loss of accommodation
77
when are pharmacologic effects more pronounced in skeletal muscle
low doses
78
how do reversible cholinesterase inhibitors affect cardiac tissue
hypotension
bradycardia
arrhythmia
79
how do reversible cholinesterase inhibitors affect the bladder and lungs
bronchoconstriction
contraction of the urinary bladder (detrusor muscle)
80
what is physostigmine used to treat
glaucoma
impaction in cattle
81
what drug combination is used to prevent or breakdown of synechia formed between lens and iris
physostigmine + atropine
82
which reversible cholinesterase inhibitors are used to treat myasthenia gravis and anticurare
neostigmine
pyridostigmine
83
which reversible cholinesterase inhibitor is used to differentiate myasthenia gravis from cholinergic crisis
edrophonium
84
when should reversible cholinesterase inhibitors use be avoided
impaction with possible mechanical obstruction
pregnancy
85
which reversible cholinesterase inhibitor depresses the CNS at large doses and causes convulsions at massive doses
physostigmine
86
which reversible cholinesterase inhibitor can cause skeletal muscle weakness in cases of overdose
neostigmine
87
what are some possible respiratory repercussions of reversible cholinesterase inhibitors
respiratory paralysis
increased bronchiolar secretion
88
what is the antagonist to reversible cholinesterase inhibitors
atropine
89
what is the irreversible cholinesterase inhibitor
organophosphourous compounds
90
True or False:
organophosphourous compounds can cross the brain blood barrier
true
91
what is the antidote used for organophosphorus poisoning
atropine
92
which organophosphorus compound is used to reactivate ChE
pralidoximine
93
True or False:
Use of pralidoxime and atropine is a time-sensitive treatment for organophosphate poisoning
true
94
for what type of poisoning should pralidoxime not be used
carbamate poisoning
95
what are some precautions that should be taken before administering pralidoxime or atropine
-no exposure to other cholinesterase inhibitor drugs
-history of respiratory illness or hepatic disease
-pregnant patients
96
how do cholinergic antagonists work
inhibit actions of acetyl choline by blocking cholinergic receptors
97
what receptors do cholinergic antagonists act on
muscarinic
Nm receptors
98
what is the response of using a cholinergic antagonist on a muscarinic receptor
muscle relaxation
99
how do antimuscarinic agents work
inhibit muscarinic actions of acetylcholine and related cholinergic agonists
100
what is the affect of atropine on the cardio vascular system
tachycardia
increased cardiac output
increased blood pressure
101
what is the response of atropine in the GIT
relaxation of GIT
decrease in motility
decrease in secretions
102
what is the affect of atropine on the urinary system
relaxes smooth muscle of bladder
urinary retention
103
what is the affect of atropine on the respiratory system
decreased secretions
bronchodilation
104
what is the affect of atropine on the ocular system
increased intraocular pressure
105
True or False:
atropine has minimal effect on the CNS
true
106
which species is resistant to atropine
rabbits
107
what atropine derivative causes slight sedation and antiemetic effects
scopolamine
108
how is atropine poisoning tested for
drop of urine
mydriasis in cat eyes
109
what is the treatment of atropine poisoning
neostigmine
physostigmine
110
which antimuscarinic drug can be used to reduce gastric acid secretion
pirenzepine
111
which antimuscarinic drug can be used for ophthalmic purposes
tropicamide
112
what is tropicamide used to treat
adhesion between iris and lens
113
what is the antidote for cholinergic agonists
atropine
114
what antimuscarinic drug can be used to prevent motion sickness
scopolamine
115
which antimuscarinic drug can be used as a preanaesthetic in veterinary medicine
glycopyrrolate
