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Flashcards in Pharmacology of the ANS Deck (71)
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1
Q

What is the orgin of the fibres in the sympathetic ANS?

A
  • Preganglionic
    • Thoracolumbar
  • Postganglionic
    • Paravertebral chain
    • Prevertebral ganglia
2
Q

What is the origin of fibres in the parasympathetic ANS?

A
  • Preganglionic
    • Craniosacral
  • Postganglionic
    • In or near target organ
3
Q

What is the purpose of autonomic reflex arcs?

A

Visceral control. The path of afferent fibres can explain referred pain.

4
Q

What are the effects on the heart of sympathetic and parasympathetic innervation?

A
  • Parasympathetic
    • Decreased heart rate
  • Sympathetic
    • Increased heart rate
    • Increased force of contraction
5
Q

What are the effects on the digestive tract of sympathetic and parasympathetic innervation?

A
  • Parasympathetic
    • Increased motility and secretion
  • Sympathetic
    • Decreased motility and secretion
6
Q

What are the effects on the lungs of sympathetic and parasympathetic innervation?

A
  • Parasympathetic
    • Bronchoconstriction
  • Sympathetic
    • Bronchodilation
7
Q

What are the effects on the urinary bladder of sympathetic and parasympathetic innervation?

A
  • Parasympathetic
    • Release of urine
  • Sympathetic
    • Urinary retention
8
Q

What are the effects on the pupil of the eye of sympathetic and parasympathetic innervation?

A
  • Parasympathetic
    • Constricts
  • Sympathetic
    • Dilates
9
Q

What are the effects on the male sexual organs of sympathetic and parasympathetic innervation?

A
  • Parasympathetic
    • Erection
  • Sympathetic
    • Ejaculation
10
Q

What are the effects on the blood vessels of sympathetic and parasympathetic innervation?

A
  • Parasympathetic
    • No effect (mostly)
  • Sympathetic
    • Constriction (mostly)
11
Q

What are the effects on the salivary glands of sympathetic and parasympathetic innervation?

A
  • Parasympathetic
    • Increased secretion
  • Sympathetic
    • Increased secretion
12
Q

What are the effects on the sweat glands of sympathetic and parasympathetic innervation?

A
  • Parasympathetic
    • No effect
  • Sympathetic
    • Increased secretion
13
Q

What are the effects on the liver of sympathetic and parasympathetic innervation?

A
  • Parasympathetic
    • No effect
  • Sympathetic
    • Glycogenolysis
    • Gluconeogenesis
14
Q

Describe the role of the ANS in the eye.

A
  • Pupillary dilator muscle
    • ​Sympathetic innercation only - mydriasis
  • Pupillary constrictor muscle
    • ​Parasympathetic innervation - miosis

NB - when there is a blockage in the canal of Schlemm, could either use an agonist of the parasympathetic NS or an antagonist of the sympathetic NS.

15
Q

Describe the role of the ANS in the urinary bladder.

A
  • When the bladder is filling:
    • Sympathetic control predominates
      • Relaxation of detrusor muscle
      • Contraction of internal sphincter muscle
  • When the bladder is full:
    • Parasympathetic control predominates
      • Contraction of detrusor muscle
      • Relaxation of internal sphincter muscle
16
Q

Which neurotransmitter is released by all preganglionic neurons in the parasympathetic and sympathetic systems?

Which receptors does it affect?

A

Acetylcholine

Acts on nicotinic receptors

17
Q

Which neurotransmitter is released by all postganglionic parasympathetic neurons?

Which receptors does it affect?

A

Acetylcholine

Acts on muscarinic receptors

18
Q

Which neurotransmitter is released by most postganglionic sympathetic neurons?

A

Noradrenaline

Some release ACh (i.e. sweat glands)

19
Q

List the predominate locations of nicotinic ACh receptors.

A
  • Neuromuscular junction
  • Sympathetic ganglia
  • Parasympathetic ganglia
  • Central nervous system
20
Q

List the predominate locations of muscarinic ACh receptors.

A
  • Parasympathetic target organs
  • Sweat glands (sympathetic)
  • Vascular smooth muscle
  • Central nervous system
21
Q

What are the main locations of M1 (neural) muscarinic receptors?

A
  • Autonomic ganglia
  • Glands
    • Gastric
    • Salivary
    • Lacrimal
22
Q

What is the main location of M2 (cardiac) muscarinic receptors?

A

Heart: atria

23
Q

What are the main locations of M3 (glandular / smooth muscle) muscarinic receptors?

A
  • Exocrine glands
    • Gastric
    • Salivary
  • Smooth muscle
    • GI tract
    • Eye
    • Airways
    • Bladder
  • Blood vessels
    • Endothelium
24
Q

What are the cellular and functional responses of the M1 muscarinic receptors?

A
  • Cellular response
    • Increased IP3
    • DAG
  • Functional response
    • Gastric secretion
25
Q

What are the cellular and functional responses of the M2 muscarinic receptors?

A
  • Cellular response
    • Decreased cAMP
  • Functional response
    • Decreased heart rate
26
Q

What are the cellular and functional responses of the M3 muscarinic receptors?

A
  • Cellular response
    • Increased IP3
    • DAG
  • Functional response
    • Gastric secretion
    • Salivary secretion
    • GI smooth muscle contraction
    • Ocular accommodation
    • Vasodilation
27
Q

Give 2 examples of muscarinic ACh receptor agonists.

A
  • Pilocarpine
  • Bethanechol
28
Q

What are the pharmalogical properties of pilocarpine?

A

Non-selective muscarinic agonist

29
Q

What are the pharmacological properties of bethanechol?

A

Non-selective muscarinic agonist.

30
Q

What are the clinical uses of pilocarpine?

A
  • Constriction of pupils (miosis)
  • Glaucoma (to decrease intraocular pressure)
  • Xerostomia (following head/neck radiotherapy)
31
Q

What are the clinical uses of bethanechol?

A
  • Bladder hypotonia
  • Gastrointestinal hypotonia
32
Q

List 6 muscarinic ACh receptor antagonists.

A
  • Atropine
  • Glycopyrronium
  • Hyoscine hydrobromide
  • Hyoscine butylbromide
  • Ipratropium
  • Tropicamide
33
Q

What are the pharmalogical properties and clinical uses of atropine?

A
  • Pharmalogical properties
    • Non-selective antagonist
    • Well absorbed orally
    • CNS effects
  • Clinical uses
    • Adjunct for anaesthesia
    • Anticholinesterase poisoning
    • Bradycardia, cardiac arrest
34
Q

What are the pharmalogical properties and clinical uses of glycopyrronium?

A
  • Pharmacological properties
    • Similar to atropine
    • Does not cross the blood-brain barrier
  • Clinical uses
    • Similar to atropine
35
Q

What are the pharmalogical properties and clinical uses of hyoscine hydrobromide?

A
  • Pharmacological properties
    • Similar to atropine
    • CNS effects
  • Clinical uses
    • Hypersalivation
    • Motion sickness
36
Q

What are the pharmalogical properties and clinical uses of hyoscine butylbromide?

A
  • Pharmacological properties
    • Similar to atropine but poorly absorbed
    • Does not cross the blood-brain barrier
  • Clinical uses
    • Gastrointestinal spasms
37
Q

What are the pharmalogical properties and clinical uses of ipratropium?

A
  • Pharmacological properties
    • Delivered via inhaler or nebuliser
    • Does not cross blood brain barrier
  • Clinical uses
    • Maintenance treatment of chronic obstructive pulmonary disease (COPD)
38
Q

What are the pharmalogical properties and clinical uses of tropicamide?

A
  • Pharmacological properties
    • Similar to atropine but shorter acting
  • Clinical uses
    • Opthalmic use (mydriasis)
39
Q

What are the general problems of selectivity with antagonists?

A
  • Few differentiate between subtypes effectively.
  • Muscarinic ACh receptors are widespread, therefore side effects.
  • Control is by route of administration and distribution.
40
Q

Give 3 examples of catecholamines.

A
  • Dopamine
  • Noradrenaline
  • Adrenaline
41
Q

What are the basic properties of dopamine?

A
  • Neurotransmitter and neuromodulator
  • Involved with:
    • Pleasure
    • Addiction
    • Movement
  • Synthesised in the bouton and inactivated principally by re-uptake .
42
Q

What are the basic properties of noradrenaline?

A
  • Sympathetic neurotransmitter.
  • Decrease is potentially associated with Parkinson’s and ADHD.
  • Synthesised in the bouton and inactivated principally by re-uptake.
43
Q

What are the basic properties of adrenaline?

A
  • Sympathetic
  • Peripheral hormone from the adrenal medulla
  • Synthesised in the bouton and inactivated principally by re-uptake
44
Q

Describe the control of noradrenaline release.

A
  • Release of noradrenaline facilitated by Ca2+
  • There are α2 adrenoceptors on the presynaptic terminal
    • Decreased Ca2+ influx = decreased noradrenaline release
  • There is no equivalent to acetylcholinesterases for noradrenaline.
    • ~75% recaptured by neurons
    • Norepinephrine transporter
    • “Repackaged” by vesicular monoamine transporter
45
Q

Give an example of a drug which affects catecholamine synthesis.

A

Methyldopa

46
Q

Give examples of drugs that affect catecholamine release and state their mechanism of action.

A
  • Amphetamines - indirectly acting sympathomimetics
  • Clonidine - acts on α2 adrenoceptors
47
Q

Give examples of drugs which inhibit catecholamine uptake.

A
  • NET inhibitors
    • Cocaine
    • Tricyclic antidepressants
48
Q

Give an example of an inhibitor of catecholamine metabolic degradation.

A

Monoamine oxidase inhibitors used in depression.

49
Q

Describe the sympathetic innervation of the adrenal gland.

A
  • Preganglionic sympthetic fibres synapse on chromaffin cells.
  • Chromaffin cells release adrenaline (~80%) and noradrenaline (~20%) into systemic circulation.
  • This results in a widespread tissue response.
50
Q

What is the classification of ANS adrenergic receptors?

A

Adrenergic receptors are metabotropic (G-protein coupled receptors).

51
Q

What is the clinical significance of the difference between alpha and beta adrenoceptors?

A

There are exploitable differences in the selectivity of these receptors for catecholamines.

There are general patterns of tissue distribution that allow for some specificity of drug action.

52
Q

What are the main ANS locations of α1 adrenoceptors?

A
  • Cardiovascular
  • GI tract
  • Genitourinary
53
Q

What is the functional ANS response of α1 adrenoceptors?

A
  • Vasoconstriction
  • Smooth muscle contraction
    • GI sphincters
    • Genitourinary
54
Q

What are the main ANS locations of α2 adrenoceptors?

A

Neuronal

55
Q

What is the functional ANS response of α2 adrenoceptors?

A

Decreased transmitter release

56
Q

What are the main ANS locations of β1 adrenoceptors?

A
  • Heart
  • Kidneys
57
Q

What is the functional ANS response of β1 adrenoceptors?

A
  • Increasing cardiac rate
  • Increasing cardiac force
  • Decreasing uring production (via renin release)
58
Q

What are the main ANS locations of β2 adrenoceptors?

A
  • Lungs
  • Smooth muscle
  • Skeletal muscle
59
Q

What is the functional ANS response of β2 adrenoceptors?

A
  • Bronchodilation
  • Relaxation of visceral smooth muscle
  • Vasodilation (skeletal muscle)
  • Tremor
60
Q

What are the pharmacological properties and clinical uses of adrenaline?

A
  • Pharmacological properties
    • Non-selective
  • Clinical uses
    • Acute anaphylaxis
    • Cardiopulmonary resuscitation
    • Acute hypotension
61
Q

What are the pharmacological properties and clinical uses of phenylephrine?

A
  • Pharmacological properties
    • α1 selective
  • Clinical uses
    • Decongestant
    • Mydriasis (to dilate pupil)
    • Acute hypotension
62
Q

What are the pharmacological properties and clinical uses of clonidine?

A
  • Pharmacological properties
    • α2 selective
  • Clinical uses
    • Hypertension
63
Q

What are the pharmacological properties and clinical uses of salbutamol?

A
  • Pharmacological properties
    • β2 selective
  • Cinical uses
    • Asthma (short acting beta agonist)
    • Uncomplicated premature labour
64
Q

What are the pharmacological properties and clinical uses of salmeterol?

A
  • Pharmacological properties
    • β2 selective
  • Clinical uses
    • Asthma (long acting beta agonist)
65
Q

What are the pharmacological properties and clinical uses of dobutamine?

A
  • Pharmacological properties
    • β1 selective
  • Clinical uses
    • Heart failure and cardiogenic shock
66
Q

List 6 examples of adrenergic receptor agonists.

A
  • Adrenaline
  • Phenylephrine
  • Clonidine
  • Salbutamol
  • Salmeterol
  • Dobutamine
67
Q

List 4 examples of adrenergic receptor antagonists.

A
  • Phentolamine
  • Prazosin
  • Propranolol
  • Atenolol
68
Q

What are the pharmacological properties and clinical uses of phentolamine?

A
  • Pharmacological properties
    • Non-selective
  • Clinical uses
    • Hypertensive episodes due to phaeochromocytoma (e.g. during surgery).
69
Q

What are the pharmacological properties and clinical uses of prazosin?

A
  • Pharmacological properties
    • α1 selective
  • Clinical uses
    • Benign prostatic hyperplasia
    • Hypertension
70
Q

What are the pharmacological properties and clinical uses of propranolol?

A
  • Pharmacological properties
    • β1 and β2 selective
  • Clinical uses
    • Hypertension
    • Angina
    • Anxiety with symptoms such as palpitations, sweating and tremor
71
Q

What are the pharmacological properties and clinical uses of atenolol?

A
  • Pharmacological properties
    • β1 selective
  • Clinical uses
    • Hypertension
    • Angina