ANS Pharmacology Flashcards
1
Q
What endogenous ligand activates nicotinic receptors?
A
Acetylcholine
2
Q
Where are nicotinic receptors located?
A
Centrally
Ganglia
Neuromuscular junctions
3
Q
What endogenous ligand activates muscarinic receptors?
A
Acetylcholine
4
Q
Where are muscarinic receptors located?
A
M1: centrally
M2: heart (inhibitory)
M3, M4: Smooth muscle and glands
M5: ??
5
Q
What is the effect of a muscarinic agonist on the eye?
A
Pupillary constriction (miosis)
6
Q
What is the effect of a muscarinic agonist on the bronchi?
A
Bronchoconstriction
7
Q
What is the effect of a muscarinic agonist on the GIT?
A
Increased secretion and motility
8
Q
What is the effect of a muscarinic agonist on the salivary glands?
A
Increased secretion
9
Q
What is the effect of a muscarinic agonist on the heart?
A
Decreased HR
10
Q
What is the effect of a muscarinic agonist on the bladder?
A
Urination
11
Q
Does acetylcholine function in the sympathetic or parasympathetic system?
A
Parasympathetic
12
Q
What family of drugs does pilocarpine belong to?
A
Muscarinic agonist
13
Q
What are the uses of pilocarpine?
A
Myosis (pupil constriction)
Used in conjunction with mydriatics (dilators) to prevent adhesions in infection
Treatment of glaucoma?
14
Q
What class of drugs does bethanechol belong to?
A
Muscarinic agonist
15
Q
What disease might you use Bethanechol for?
A
FLUTD cats (stimulates detrusor muscle contraction and bladder emptying)
16
Q
What are the side effects of bethanechol?
A
Stimulates GIT movement
Pupil constriction (myosis)
Increased bronchoconstriction and secretions
Reduced HR
17
Q
Name four muscarinic agonists
A
Methacholine
Bethanechol
Pilocarpine
Carbachol
18
Q
Which two muscarinic agonists have the strongest effects on GIT motility and bladder contraction?
A
Bethanechol
Carbachol
19
Q
Which muscarinic agonist has the strongest effects on GIT and the pupil?
A
Pilocarpine
20
Q
Which muscarinic agonist has the largest effect on heart rate?
A
Methacholine
21
Q
Which class of drugs does atropine belong to?
A
Muscarinic antagonist (parasympatholytics)
22
Q
Which class of drugs does scopolamine belong to?
A
Muscarinic antagonist (parasympatholytics)
23
Q
Which class of drugs does glycopyrrolate belong to?
A
Muscarinic antagonist (parasympatholytic)
24
Q
What drug class does propantheline belong to?
A
Muscarinic antagonist (parasympatholytics)
25
Which muscarinic antagonist does not cross the blood-brain barrier?
Propantheline
26
What are the actions of anti-muscarinics?
Increase HR
Dry up secretions (lacrimal, salivary, bronchial)
Dilate pupil
Urinary retention
Decrease bronchoconstriction
Reduce GIT motility
27
What are the indications of anti-muscarinics?
Premedicant to prevent bradycardia in anaesthesia
Minimise respiratory secretions
Antidote to cholinesterase inhibitor (organophosphates)
28
Name four competitive nicotinic antagonists
Curare
Pancuronium
Atracuronium
Vecuronium
29
Name a nicotinic agonist used as a depolarising agent
Suxamethonium
30
Name two agents that prevent release of Ach
Botulinum
Aminoglycoside antibiotics
31
What is the action and indication of a muscular antagonist (nicotinic)
paresis/paralysis
To assist with mechanical ventilation (e.g. anaesthesia)
32
Can vecuronium/pancuronium be reversed?
Yes, by cholinesterase inhibitors
33
What is suxamethonium used for?
e.g. intubation (paralysis of laryngeal muscles)
34
Describe the action of botulinum toxin
Prevents release of Ach from presynaptic membrane (irreversible)
35
Describe the pathogenesis of myasthenia gravis
1. Genetic defect resulting in low numbers of nicotinic receptors
2. Aquired autoimmune disease resulting in antibody destruction of nicotinic receptors
36
What drug class can be used in the treatment of myasthenia gravis?
Cholinesterase inhibitors
37
Name three cholinesterase inhibitors
Physostigmine
Neostigmine
Edrophonium
38
What drug class is physostigmine?
Cholinesterase inhibitor
39
What drug class does neostigmine belong to?
Cholinesterase inhibitor
40
What drug class does Edrophonium belong to?
Cholinesterase inhibitor
41
What drug class does curare belong to?
Competitive nicotinic antagonist
42
Describe the mechinism of action of pancuronium
competitive nicotinic antagonist
43
Describe the mechanism of action of atracuronium
competitive nicotinc antagonist
44
Describe the mechanism of action of vecuronium
competitive nicotinic antagonist
45
Describe the mechanism of action of suxamethonium
Nicotinic agonist (depolarising agent)
46
Describe the mechanism of action of aminoglycosides
Prevents release of acetylcholine
47
Name other compounds that inhibit cholinesterase
Organophosphates
Some pesticides
Some herbicides
Nerve gases
Some anthelminthics
48
What does SLUDGE refer to?
Symptoms of AChE inhibitor poisoning
Salivation
Lacrimation
Urination
Defecation
Gastrointestinal problems
Emesis
49
What is the antidote for OP poisoning?
Atropine
50
Describe the location and action of alpha 1 adrenoreceptors
Mainly smooth muscle
Release of intracellular Ca++: muscle contraction
51
Describe the location and action of alpha 2 adrenoreceptors
Located presynaptically
Pre-synaptic inhibition of NA release
52
Describe the location and action of beta 1 adrenoreceptors
Primarily in cardiac muscle
Increased Ca++ conductance: Increased HR and contractility
53
Describe the location and action of Beta 2 adrenoreceptors
Located on smooth muscle
Phosphorylation of intracellular proteins: muscle relaxation
54
Describe the location and action of Beta 3 adrenoreceptors
Mainly on adipose tissue
Lipolysis and thermogenesis
55
What are the primary sympathetic receptor type(s) and effects in cardiac muscle
Beta 1 adrenoreceptors
Increased HR and force
56
What are the primary sympathetic receptor types and effects on blood vessels?
(Skin, viscera) alpha 1 adrenoreceptors -\> constriction
(Skeletal muscle) Beta 2 adrenoreceptors -\> dilation
57
What are the primary sympathetic receptor types and effects on bronchi?
Beta 2 adrenoreceptors: bronchodilation
58
What are the primary sympathetic receptor types and effects in the GIT?
(Smooth muscle): alpha 1, alpha 2, beta 2: decreased motility
(Sphincters): alpha 2, beta 2: constriction
59
What are the primary sympathetic receptor types and effects in the bladder?
(Smooth muscle) Beta 2: relaxation
(Sphincter) Alpha 1: contraction
60
What are the primary sympathetic receptor types and effects in the eye?
(Pupil) alpha 1: contraction of radial muscles -\> dilation of pupil
(Ciliary muscle) beta 2: relaxation (far vision)
61
What are the primary receptor types and effects in sweat glands
M3 (muscarinic)
Secretion
62
What are the primary sympathetic receptor types and effects in the liver
alpha 1, beta 2
glycogenolysis, gluconeogenesis
63
Adrenaline has affinity for which receptors?
+++ Beta 1, Beta 2
++ Alpha 1, Alpha 2
64
Noradrenaline has affinity for which receptors?
+++ Alpha 1, Alpha 2
++ Beta 1, Beta 2
65
Dopamine has affinity for which receptors?
++ Alpha 1, Alpha 2, Beta 1, Beta 2,
Dopamine
66
Salbutamol has affinity for which receptors?
+++ Beta 2
+ Beta 1
(no action at alpha receptors)
67
Phenylephrine has affinity for which receptors?
++ alpha 1, alpha 2
| (no action at beta receptors)
68
Xylazine has affinity for which receptors
++ alpha 2
| (selective)
69
What are the main uses for adrenaline?
Increase HR, bronchodilation
70
What are the main (peripheral) uses for dopamine?
Increased HR and BP
71
What are the main uses for salbutamol?
Bronchodilation
72
What are the main uses for phenylephrine?
Increase BP, constriction of vessels in nose (decrease secretions), local control of bleeding
73
What is the main use of xylazine?
Anaesthesia/sedation
74
Why would epinephrine be used with a local anaesthetic?
Reduce perfusion and prolong action
SHOULD NOT BE USED ON EXTREMITIES
75
Name two selective alpha 1 agonists
Phenylpropranolamine (Propalin)
Pseudoephedrine
76
Name a use for Phenylpropranolamine (Propalin) or Pseudoephedrine
Urinary incontinence
77
List four alpha2 agonists
Xyalzine
Medetomidine
Demetomidine
Romifidine
78
What is the mechanism of action of xylazine?
Alpha 2 agonist
79
What is the mechanism of action of Medetomidine?
Alpha 2 agonist
80
What is the mechanism of action of Demetomidine?
Alpha 2 agonist
81
What is the mechanism of action of Romifidine?
Alpha 2 agonist
82
Name two alpha 2 antagonists
Yohimbine
Atipamezole
83
What is the mechanism of action of yohimbine?
Alpha 2 antagonist
84
What is the mechanism of action of Atipamezole?
Alpha 2 antagonist
85
Name a use for alpha 2 antagonists
Reversal of alpha 2 agonists (reversal of sedation)
86
Describe how an alpha 2 agonist causes sedation
Agonist at alpha 2 receptors, which are located on presynaptic membrane
Reduces release of noradrenaline
Decreased action of noradrenaline at postsynaptic alpha receptors
87
Name a selective beta 1 agonist
Dobutamine
| (does have action at other receptors at high doses)
88
What can dobutamine be used for
Post cardiac arrest (positive inotrope)
Maintain HR and BP in surgery
89
Name three selective Beta 2 agonists
Salbutamol
Terbutaline
Clenbuterol
(Does have a small amount of activity at Beta 1 also\_
90
What is the mechanism of action of dobutamine
(Selective) Beta 1 agonist
91
What is the mechanism of action of salbutamol?
(Selective) Beta 2 agonist
92
What is the mechanism of action of salbutamol?
(Selective) Beta 2 agonist
93
What is the mechanism of action of terbutaline?
(Selective) Beta 2 agonist
94
What is the mechanism of action of clenbuterol?
(Selective) Beta 2 agonist
95
What are the indications of Beta 2 agonists?
Feline asthma
Chronic obstructive pulmonary disease (horses)
96
Name three non-selective Beta agonists
Adrenaline
Noradrenaline
Isoprenaline
97
What is the mechanism of action of isoprenaline?
Non-selective beta agonist
98
Name two non-selective alpha adrenoreceptor antagonists (sympatholytics)
Phenoxybenzamine
Phentolamine
99
Name a non-selective beta adrenoreceptor antagonist
Propranolol
100
What is the action of phenoxybenzamine?
alpha 1 and 2 antagonist
101
What is the action of phentolamine?
alpha 1 & 2 antagonist
102
What is the action of propranolol?
Beta 1 and 2 antagonist
103
Name an alpha 1 antagonist
Prazosin
104
What is the mechanism of action of prazosin?
Alpha 1 antagonist
105
Name two Beta 1 antagonists
Atenolol
Metoprolol
106
What is the mechanism of action of atenolol?
Beta 1 antagonist
107
What is the mechanism of action of metoprolol
Beta 1 antagonist
108
What are the uses for prazosin?
hypertension, congestive heart failure, relax urinary sphincter
109
What are indications for beta antagonists?
tachycardia
atrial fibrillation
hypertrophic heart disease
110
What are some possible side effects of non-selective beta blockers?
Increased bronchoconstriction (asthma?)
Decrease cardiac contraction (heart problems?)
Block glycogenolysis (hypoglycaemic/diabetic?)
111
What is the function of monoamine oxidase (MAO)?
Catabolism of adrenaline, noradrenaline, dopamine
112
What is an indication for adrenaline?
Anaphylactic shock
113
Name four muscarinic antagonists
Atropine
Hyoscine (scopolamine)
Glycopyrrolate
Propantheline
114
Are muscarinic antagonists competitive or non-competitive?
Competitive
