Patient: Cholinergic drugs Flashcards Preview

Pharmacy Year 2 Semester 1 > Patient: Cholinergic drugs > Flashcards

Flashcards in Patient: Cholinergic drugs Deck (39):
1

Difference between muscarinic and nicotinic acetylcholine receptors

Muscarinic: G-protein coupled, slow
Nicotinic: ligand-gated ion channel, fast transmission

2

Name 3 sites of action for nicotinic acetylcholine receptors

CNS, NMJ, autonomic ganglia

3

Name 3 sites of action for muscarinic acetylcholine receptors

CNS, Parasympathetic nervous system, sympathetic nervous system

4

Describe nicotinic acetylcholine receptors using this:
1) -meric
2) number of subunits and receptor subtypes
3) built in/g protein
4)number of Ach sites
5) speed of response

1) Pentameric
2) 18 subunits of multiple types
3) built in ion channel
4) 2 Ach sites
5) microseconds to milliseconds

5

Describe muscarinic acetylcholine receptors using this:
1) -meric
2) number of subunits and receptor subtypes
3) built in/g protein
4)number of Ach sites
5) speed of response

1) Monomeric
2) M1-5 subtypes, 5 receptor sites
3) Binding site for G protein
4) 1 Ach site
5) milliseconds to seconds

6

Agonists of nicotinic acetylcholine receptors

nicotine, suxamethonium

7

Antagonists of nicotinic acetylcholine receptors

atracurium, tubocurarine, alpha-bugarotoxin

8

Agonists of muscarinic acetylcholine receptors

pilocarpine, muscarine

9

Antagonists of muscarinic acetylcholine receptors

atropine, hyoscine

10

Drugs acting at ACh

Paralyzing agents used in surgery*
Drugs to treat nicotine addiction*
Anti-emetic drugs*
Anti-asthma drugs*
Drugs used in eye exams
Drugs used to treat glaucoma
?Alzheimer’s disease drugs*
?Parkinson’s disease drugs
?Anti-schizophrenia drugs

11

Drugs acting on ACh metabolism/release

ACh esterase (AChE)
Drugs to treat myasthenia gravis*
Drugs to treat Alzheimer’s disease*
Drugs to treat glaucoma
Nerve gases, insecticides*
ACh release
Botox*

12

Name two type of blockers to neuromuscular transmission
(mechanism-wise)

Competitive antagonists at nAChR (flaccid paralysis)
Depolarising blockers agonists at nAChR

13

How to reverse the effect of a competitive antagonist at the nAChR

Can be reversed by AChE inhibitors

14

Can depolarising blockers (agonists at nAChR) be reversed with AChE inhibitors?

No

15

Name a use of a neuromuscular transmission blocker

muscle relaxation in surgery

16

Muscle relaxation doing surgery.. name some drugs which use the competitive antagonist of nAChR route

Atracurium
Pancuronium
Vecruonium
Gallamine
Tubocurarine

17

Muscle relaxation doing surgery.. name some drugs which use the depolarising blocker agonists at nAChR route

Suxamethonium
Decamethonium

18

What is Suxamethonium hydrolysed by? How long does it work for?

serum ChE
fast recovery - 3 minutes

19

How does Atracurium break down?

Spontaneously breaks down

20

Duration of action for Pancuronium? Uses?

100-200 minutes
Used for euthanasia and executions

21

Tell me about a receptor involved in nicotine addiction/smoking cessation

Receptor containing α4 and β2 subunits may be important in nicotine addiction
Varenicline (Champix) = partial agonist at α4β2 receptor.
NICE concludes it is cheaper long term than NRT or bupropion

22

Are agonists used with muscarinic drugs? Name two

Agonists not widely used
apart from
Pilocarpine in glaucoma
and
bethanechol in bladder disorders

23

Name 3 general effects of muscarinic antagonists

-tachycardia
-inhibits secretions (saliva, gastric acid)
-relaxes smooth muscle (GI tract, bronchi)

24

Name some therapeutic effects of muscarinic antagonists

Anti-emetic
Anti-parkinsonian
(Amnesia, sedation)

25

Name some muscarinic antagonists

Atropine
Tiotropium, ipratropium
Hyoscine
Darifenacin, solifenacin

26

Use of Atropine

Prevent bronchial secretions during surgery

27

Use of Tiotropium and ipratropium

Inhaled bronchodilators in asthma
quaternary ammonium salts so not absorbed systemically

28

Use of Hyoscine

treat motion sickness

29

Use of Darifenacin and Solifenacin

Treat M3 selective bladder hyperactivity

30

How does botulinum toxin work?

Blocks release of ACh by breaking down SNARE proteins

31

Effects of botulinum

Paralysis of skeletal muscle, autonomic block
systemic effects can cause death

32

Use of botulinum

Can be used to paralyse muscles on a local basis
muscle spasm treatment and cosmetic wrinkle removal

33

List some irreversible acetylcholinesterase inhibitors

Sarin, VX

34

What are sarin and VX used for?

irreversible acetylcholinesterase inhibitors
nerve gases and insecticides
causes muscle paralysis and over-activation of the autonomic nervous system (especially the parasympathetic route)

35

How to counteract the effects of sarin and VX

Atropine can counter some symptoms via mAChR
Pralidoxime regenerates enzyme if administered within five hours.

36

Name some competitive reversible AChEsterase inhibitors

Edrophonium
Physostigmine
Neostigmine
Rivastigmine

37

Name some non-competitive reversible AChEsterase inhibitors

Tacrine
Donepezil

38

When are reversible AChEsterase inhibitors used?

In situations where there needs to be a boost cholinergic transmission

39

Clinical uses of reversible AChEsterase inhibitors

Reversal of non-depolarizing NMJ blocker e.g. pancuronium
Autoimmune myasthenia gravis
immune attack on nAChR in NMJ. Increasing ACh boosts transmission via remaining receptors
increases muscle strength
edrophonium (test); pyridostigmine, neostigmine, physostigmine
Alzheimer’s disease
loss of cholinergic neurons
tacrine, donepezil