Chapter 7-8: Cholinoceptor Drugs

Question 1

Where are mAch-R?

Answer 1

Nerves
Heart/smooth muscle
Glands/endothelium

Question 2

Where are nAch-R?

Answer 2

NMJ
Autonomic ganglion

Question 3

Muscarine mimics effects of what NS?

Answer 3

PNS

Question 4

What can bind to the cholinoceptors?

Answer 4

Choline esters and Alkaloids

Question 5

What is Mycetism?

Answer 5

Toxicity of Muscarinic agonism
Brightly colored mushrooms

Vomiting, diarrhea, drooling, decreased HR/RR/BP, shock

Question 6

What is Tx for Mycetism?

Answer 6

Antimuscarinic:

2mg Atropine

Question 7

T/F: Nicotine only binds to nAch-R?

Answer 7

T

Question 8

Why do you see tremors when smoking?

Answer 8

Nicotine at the NMJ binds to the nAch-R causing small contractions

Question 9

What does the M1,3,5 receptors do?

Answer 9

Stimulatory
Increase phospholipase C

Question 10

What does M2,4 receptors do?

Answer 10

Inhibitory
inhibits adenylyl cyclase

Question 11

List the major clinical uses of cholinomimetic agonists

Answer 11

• Tx of Glaucoma: Carbachol/pilocarpine - reduce intraocular pressure with glaucoma
• MG: neostigmine/pyridostigmine- improve muscle strength by increasing acetylcholine levels at NMJ

-Alzheimer’s: Cholinesterase INHIBITOR donepezil - manage symptoms by enhancing cholinergic function in the brain

-Postoperative Ileus and Urinary Retention: Bethanechol- stimulate bowel and bladder function

-Xerostomia (Dry Mouth): Pilocarpine and cevimeline- stimulate salivary secretion in patients with dry mouth, often due to Sjögren’s syndrome or radiation therapy.

Question 12

Tx of Glaucoma

Answer 12

Carbachol/pilocarpine

Question 13

Management of MG:

Answer 13

-stigmine

Question 14

Management of Alzheimers

Answer 14

donepezil

Question 15

Postoperative Ileus and Urinary Retention Tx

Answer 15

Bethanechol

Question 16

Dry mouth Tx:

Answer 16

“Xerostomia”

Pilocarpine
cevimeline

Question 17

T/F: Esters of Choline cross barriers easily

Answer 17

F

Large and charged. insoluble in lipids and doesnt cross barriers easily

Question 18

Describe the Pharmacokinetics for Esters of Choline

Answer 18

A: poor
D: poor
M: -Ach: rapid (5-20 secs)
- Methacholine: 3x longer
- Carbachol/Bethanechol - resistant to hydrolysis: 4 min to hours

Question 19

What is the Betel nut?

Answer 19

Arecoline Alkaloid

similar effects to nicotine

used alot in various places in the world and has a red color

Question 20

Nicotine is very ____ soluble

Answer 20

lipid

Question 21

Nicotine stimulates _______ NS

Answer 21

ALL OF THE

Question 22

Which NS responses dominate the others in response to nicotine?

Answer 22

Sympathetic

Question 23

Describe Pharmacokinetics with Alkaloids

Answer 23

A: Pilocarpine, Nicotine, Lobeline
(-INE)!!!!!!!!! - well
-Muscarine - charged so less well
E: Kidneys- enhanced by acidification of urine

Question 24

T/F: Atropine in Open Angle glaucoma is contraindicated and is a medical emergency

Answer 24

F

Closed-angle (Narrow angle)

Question 25

What is glaucoma?

Answer 25

excess intraocular fluid

Question 26

cholinomimetics Organ effects: Eye

Answer 26

Constriction of pupil "miosis" **Increases intraocular drainage**

Question 27

cholinomimetics Organ effects: CVS

Answer 27

-Reduction in peripheral vascular resistance -vasodilation -decrease BP -reflex tachycardia **large doses bradycardia**

Question 28

cholinomimetics Organ effects: Respiratory

Answer 28

bronchials contract secretions increased

Question 29

cholinomimetics Organ effects: GI

Answer 29

Increased GI activity relaxed sphincter

Question 30

cholinomimetics Organ effects: CNS

Answer 30

release dopamine, serotonin, GABA, NE enhance cognitive functions

Question 31

Define the different types of glaucoma and the use of cholinomimetics

Answer 31

Open angled: cholinomimetic drugs like pilocarpine can constrict the pupil and increase drainage through the canal of Schlemm. Closed angled: the iris is pushed forward, cholinomimetics can worsen the condition by further constricting the angle and impeding drainage. This can lead to a medical emergency.

Question 32

cholinomimetics Organ effects: NMJ

Answer 32

immediate depolarization of end plate muscle contraction

Question 33

What is depolarization blockade?

Answer 33

When the cell is continuously being depolarized and cant repolarize causing flaccid paralysis Ex) Succs