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Flashcards in L2 Deck (36):
1

Remind yourself... what are the muscarinic receptors? Where are they?

CHOLINGERIC receptors - bind ACh!!!
M1 - ganglia - slow EPSP
M2
- Ganglia - IPSP
- Heart = ↓HR & contractility
M3 - on GI, eyes, BVs, etc
- Smooth muscle contraction
- Gland secretion

2

Are muscarinic receptors ion channels or GCPRs?

7TM GCPR
M1 & 3 - Gq
M2 - Gi

3

Which muscarinic receptors are found in the GI? Fxn of each.

M3 - mediates smooth muscle contraction = motility; secretions
M2 - inhibits relaxation
Working together to maintain basal parasympa tone

4

Which muscarinic receptors are found in BVs? Fxn of each?

Usually para sympa has no influence on BVs
But BVs do express M3 receptors that bind circulating ACh (not directly innervated by para) to aid relaxation

5

What is the fxn of muscarinic receptors at sphincters?

M3 (M1?) = relax sphincter

6

What are the 4 muscarinic agonists?

Carbamylcholine
Acetyl-beta-methylcholine
Bethanechol
Pilocarpine

7

Which muscarinic agonist works at the heart? What would the effects there be?

Acetyl-beta-methylcholine
Net parasympa tone

8

What muscarinic agonist works at the GI, bladder, and eye but is muscarinic only (vs nicotinic > muscarinic)?

Bethanechol

9

What muscarinic agonist works at the GI, bladder, eye, and is nicotinic > muscarinic?

Caramylcholine

10

Which muscarinic agonist is hydrophobic and used to treat the eye?

Pilocarpine

11

Which 2 muscarinic agonists are resistant to AChE hydrolysis?

Resistant = bethanechol & carbamylcholine
Slow AChE hydrolysis = ABM

12

What is the mneumonic for parasympa overstim = OD on muscarinic agonists?

SLUDE
Salivation
Lacrimation
Uriniation
Defication
GI motility
Emesis = vomiting

13

What are the cardiovas symptoms of para overstim?

Hypotension - M3 vasodilation
Bradycardia - M2 at SA node and myocardium

14

What are the resp symptoms of para overstim?

Bronchoconstriction
↑secretions
Both M3

15

What are the GI symptoms of para overstim?

Vomiting
Ab cramps - activated smooth muscle

16

What are the gland symptoms of para overstim?

↑Saliva, lacrimation, sweating

17

What are the ocular symptoms of para overstim?

Constricted pupil - M3 on sphincter muscle
Spasm of accomidation - M3 @ ciliary body

18

Explain the use of pilocarpine for glaucoma

Constricts circular muscles of eye - open iris - opens drainage canals

19

Why would you use a muscarinic agonist for cateract extraction?

Stretch iris for suturing room

20

What drug should you use for GI procedures? Why?

Bethanechol
Post-op obstruction, congenital megacolon, GERD
1. Create tone during surgery
2. Increase tone in sphincter to keep contents from refluxing

21

Which drug do you use for urinary retention?

Bethanechol

22

Which drug do you use for dry mouth?

Pilocarpnie applied directly to salivary gland

23

6 contraindications for using muscarinic agonists

Asthma
Hyperthyroidism - AFib
Coronary insufficiency
Peptic ulcers
Mechanical or inflam cause of GI obstruction/urinary tract
Peritonitis

24

What are the 5 non-selective muscarinic ANTagnoists?

Atropine
Scopolamine
Tropicamide
Cyclopentolate
Glycopyrrolate

25

What are the 4 selective muscarinic antagonists? What are each's affinity?

Pirenzepine - M1, medium M3
Tiotropium - M1 & M3, low M2
Tolterodine & darifenacin - M3

26

Why do you use tolterodine/darifenacin?

Detrusor muscle in bladder
Goal to constrict sphincter

27

Which muscarinic antagonist do you use for colds - why?

Ipratropium bromid
Relaxes bronchial smooth muscle

28

Why would you use anti-muscarinics for chronic rhinitis?

↑airway passage
↓secretions

29

Which muscarinic antagonists could you use for chronic bronchitis/emphysema? Why these specifically?

Increase airway passage with NO change to sputum viscosity

30

Which 2 drugs for intestinal hypermotility or diarrhea?

1. Glycopyrrolate
2. Pirenzepine

31

Which 2 drugs do you use for overactive bladder?

Darifenacin
Tolterodine
Selective for M3 receptor in detrusor muscle

32

Which 2 drugs could you use to gain airway access for intubation pre-surg, prevent vagal reflexes during surg, and to recover from anesthesia?

Glycopyrrolate = charged
Atropine = uncharged

33

Which muscarinic antagonists are used to examine the retina and optic disc?

Cyclopentolate
Tropicamide - shortest acting option!

34

Drug for motion sickness

Scopolamine prophylactically
Block M3 receptors
- Vestibular
- Vomiting center @ nucleus of solitary tract

35

3 contraindications for muscarinic antagonists

Narrow angle glaucoma
Cardiac arrhythmia
Chronic lung disease - most will be drying
- Exceptions = ipratropium & tiotropium

36

Symptoms of mushroom poisoning. treatment?

Mushrooms have muscarine - symptoms of OD:
- Perspiration
- Lacrimation
- Salivation
Treat with ATROPINE