Autonomic and NMJ Pharmacology

Question 1

What is a NMJ?

Answer 1

The connections between the efferent motor neurone and the skeletal muscle

Question 2

What happens to acetylcholine after it reaches the nicotinic receptor?

Answer 2

It is broken down by acetylcholinesterase into acetate and choline which is taken back up by the neurones and recycle into new ACh into vesicles

Question 3

What does hemicholinium do?

Answer 3

Inhibits choline transport

Question 4

What does black widow spider venom do?

Answer 4

Block voltage gated Ca ion channels

Question 5

What does botulinium toxin do?

Answer 5

Block vesicle fusion

Question 6

What does d-tubcararine do?

Answer 6

Use non-depolarising nicotinic receptor blockers

Question 7

What does succinylcholine do?

Answer 7

Use depolarising nicotinic receptor blockers

Question 8

What does 3,4-aminopyridine do?

Answer 8

Prolongs the action potential

Question 9

When are non-depolarising or depolarising blockers used for paralysis?

Answer 9

• Surgical procedures
• Electroconvulsive therapy
• Controlling spasms in tetanus

Question 10

When is botulinum toxin used?

Answer 10

• Treating muscle spasms

- Cosmetic procedures

Question 11

When is anti-cholinesterase used?

Answer 11

• Treating myasthenic syndromes

- Reversing action of non-depolarising blockers

Question 12

What does hexametheneum do?

Answer 12

Block ACh activated channel

Question 13

What does mecylamine do?

Answer 13

Non-depolarising nicotinic receptor blocker

Question 14

What does suxamethoneum do?

Answer 14

Depolarising nicotinic receptor blockers

Question 15

Ganglionic transmission

How can transmission be increased at synapses?

Answer 15

Nictotine

Question 16

What are the clinical applications for ganglionic transmission?

Answer 16

Next to none as there are too many widespread side effects

Question 17

What is atropine?

Answer 17

Muscarinic receptor antagonist

Question 18

What are examples of muscarinic receptor agonists?

Answer 18

• Carbachol

- Pilocarpine

Question 19

What do muscarinic agonists do?

Answer 19

Mimic the effect of the parasympathetic system

Question 20

What do muscarinic antagonists do?

Answer 20

Block the effects of the parasympathetic system

Question 21

What is pilocarpine used for?

Answer 21

Used in the treatment of glaucoma: high intra ocular pressurre

Question 22

What does pilocarpine do?

Answer 22

It contracts the ciliary muscle supporting the lens and seems to pen up the trabecular network through which the aqueous humour drains and/or the sphincter muscle of the iris contract which has the same effect

Question 23

What does carbidopa do?

Answer 23

Block the enzymes that produce NA

Question 24

What does reserpine do?

Answer 24

Block the transporter that fills the vesicles with NA

Question 25

What does methyldopa do?

Answer 25

Introduces a false transmitter

or activates inhibitory presynaptic autoreceptors

Question 26

What do doxazosin and propranolol do?

Answer 26

Block a or B postsynaptic receptors

Question 27

How is tyrosine converted to NA?

Answer 27

• Tyrosine to DOPA using tyrosine hydroxylase
• DOPA to dopamine using dopa decarboxylase
• Dopamine to NA using dopamine hydroxylase

Question 28

What enzyme does carbidopa block?

Answer 28

Dopa decarboxylase

Question 29

What do amphetamines ddo?

Answer 29

Stimulate NA adrenaline release

Question 30

What does phenoxybenzamine do?

Answer 30

Inhibits uptake of NA into glia

Question 31

What does cocaine and tricyclic antidepressants do?

Answer 31

Inhibits uptake of NA into neurones

Question 32

What do phenylepinephrine and salbutamol do?

Answer 32

Activate postsynaptic receptors

Question 33

What are the clinical applications for the postganglionic sympathetic transmission?

Answer 33

• a1 agonists used as decongestants and to dilate the pupil
• a2 agonists used in the treatment of hypertension
• B2 agonists used in treatment of asthma
• B1 antagonists in the treatment of hypertension, angina, cardia arrhythmias and glaucoma