4. Autonomic Pharmacology

Question 1

What are adrenergic agonists also known as?

Answer 1

Sympathomimetics

Question 2

What receptors does adrenaline work on?

Answer 2

Both a and B adrenoceptors

Question 3

What are the actions of adrenaline?

Answer 3

Vasoconstriction and cardiac stimulant
Increase systolic BP through B1
Dilate vessels in skeletal muscle through B2

Question 4

What receptors does noradrenaline work on?

Answer 4

a1 and a2, some action at B1

Question 5

What are the actions of noradrenaline?

Answer 5

Increase peripheral resistance, which increases both systolic and diastolic BP

Question 6

Name a selective a1 agonist?

Answer 6

Phenylephrine

Question 7

What are the uses of phenylephrine?

Answer 7

Vasoconstriction and increased BP

Vasopressors, nasal decongestant, pupil dilatation

Question 8

Name a B-adrenoceptor agonist?

Answer 8

Salbutamol

Question 9

What are the actions of salbutamol?

Answer 9

Vaso and broncho dilatation

Question 10

Why is salbutamol not used as an anti-hypertensive?

Answer 10

Reduced blood pressure causes reflex tachycardia

Question 11

What are adrenoceptor antagonists also known as?

Answer 11

Sympatholytics

Question 12

Name an a-receptor antagonist?

Answer 12

Phenoxybanzamide

Question 13

How does phenoxybanzamide work?

Answer 13

Binds irreversibly to receptor
Inhibits recycling of NA
Causes vasodilation at a1 so lowers BP

Question 14

Name a non-selective a-receptor antagonist

Answer 14

Phentolamine

Question 15

Why are non-selective a-receptor antagonists no longer used?

Answer 15

They induce tachycardia, dysrhythmias and increase GI activity

Question 16

What are selective a1 antagonists used for?

Answer 16

Treat hypertension

Question 17

What are the side effects of a1 antagonists?

Answer 17

Postural hypotension

Impotence

Question 18

Name 2 b-receptor antagonists

Answer 18

Propanolol

Atenolol

Question 19

What are b-receptor antagonists used for?

Answer 19

Arrhythmias
Angina
MI and post-MI

Question 20

What side effects are associated with atenolol?

Answer 20

Bronchoconstriction
Bradycardia
Cardiac Failure

Question 21

What are the types of nicotinic receptor?

Answer 21

Nm at neuromuscular junction

Nn at regions with neurotransmitters

Question 22

Which muscarinic receptors increase and decrease cell excitability?

Answer 22

M1, 3, 5 increase

M2, 4 decrease

Question 23

What enzyme breaks down ACh?

Answer 23

ACh esterase

Hydrolysed rapidly, choline is recycled and acetyl CoA from glycolysis used

Question 24

Describe the structure of nicotinic receptors

Answer 24

Ligand gated ion channels

Pentameric

Question 25

What does binding of ACh to a nicotinic receptor cause?

Answer 25

Influx of Na+ and efflux of K+ | Release of intracellular Ca++

Question 26

What pathway is utilised by M1, 3, 5?

Answer 26

Inositol triphosphate

Question 27

What pathway is utilised by M2, 4?

Answer 27

Inhibit adenylate cyclase

Question 28

Where are M1 receptors found?

Answer 28

Neural

Question 29

Where are M2 receptors found?

Answer 29

Cardiac

Question 30

Where are M3 receptors found?

Answer 30

Glands

Question 31

Name an M3 agonist

Answer 31

Pilocarpine

Question 32

What is the function of pilocarpine

Answer 32

Increase exocrine gland secretion | Used in glaucoma to help drain excess aqueous humor

Question 33

What effect does nicotine have?

Answer 33

Nicotinic agonist at low doses | Causes vasoconstriction which increases BP

Question 34

How do anti-AChE drugs work?

Answer 34

Prevent the breakdown of ACh

Question 35

What drug is used in the diagnosis of myasthenia gravis?

Answer 35

Edrophonium | Causes eyelid weakness to be temporarily relieved

Question 36

Name an anti-AChE drug that is used as a war gas?

Answer 36

Sarin | Causes SLUDGE syndrome

Question 37

What is used as an antidote to sarin?

Answer 37

Atropine

Question 38

What are the effects of anti-AChE drugs?

Answer 38

Parasympathetic effects | Increase muscle twitch

Question 39

What are cholinergic receptor antagonists used for?

Answer 39

``` Control bradycardia Dilate pupil Treat asthma Control saliva Slow GIT Anti-emesis ```

Question 40

Name a drug which is a competitive antagonist at muscarinic receptors

Answer 40

Atropine

Question 41

Name a selective M3 antagonist used in COPD and asthma

Answer 41

Ipatropium

Question 42

Name an M3 antagonist used to treat urinary incontinence

Answer 42

Darifenacin

Question 43

Name an M1 antagonist used to treat peptic ulcers

Answer 43

Pirenzepine

Question 44

What are ganglionic blocking agents?

Answer 44

Block ACh at nicotinic receptors | Have some use in hypertension

Question 45

What can neuromusclar blocking agents be divided into?

Answer 45

Depolarising and non-depolarising

Question 46

What are neuromuscular blocking agents used for?

Answer 46

Relax muscles in conjunction with anaesthesia

Question 47

How does botulin toxin work?

Answer 47

Blocks ACh release

Question 48

Name a selective a2 agonist

Answer 48

Clonidine