Muscarinic Agonists

Question 1

Describe the mechanism of diabetic autonomic neuropathy

Answer 1

metabolic insult to nerve fibers, neurovascular insufficiency, autoimmune damage, neurohomormonal growth factor deficiency

Question 2

Significance of cardiovascular autonomic neuropathy?

Answer 2

increased risk of silent myocardial ischemia/mortality

Question 3

Autonomic, mainly vagal, nerve dysfunction is common in which types of patients and it’s exaggerated by what?

Answer 3

common in patients with liver diseases and is further exaggerated by alcohol abuse

Question 4

Advanced chronic liver disease is characterized by?

Answer 4

peripheral arterial vasodilation and increased plasma catecholamine concentrations

Question 5

Botulism toxin poisoning can occur through?

Answer 5

contamination with the toxin (Clostridium botulinum), through an open wound (more commonly observed with i.v. drug users), or with bad botox injections

Question 6

Symptoms of botulism toxin poisoning?

Answer 6

weakness, trouble seeing, feeling tired, and trouble speaking (similar to myasthenia gravis)

Question 7

How does Botulism toxin work?

Answer 7

interacts with SNARE proteins preventing vesicle Ach neurotransmitter release

Question 8

What is Graves’ disease?

Answer 8

autoimmune disease where a thyroid-stimulating immunoglobulin acts like TSH and stimulates the secretion of T4 and T3

Question 9

Symptoms of Graves’ disease?

Answer 9

mimics a hyperadrenergic state - feeling hot, excessive sweating, irregular heartbeat/tachycardia, diarrhea/hyperdefecation, dry eyes, weight loss, hypertension

Question 10

How do you treat Graves’ disease?

Answer 10

treatment with beta-blockers

muscarinic agonists are contraindicated

Question 11

Glucocorticoids released by the adrenal gland inhibit the formation of what?

Answer 11

the enzyme that converts T4 -> T3

Question 12

Hashimoto’s disease

Answer 12

autoimmune disease where antibodies attack the thyroid

Question 13

Symptoms of hypothyroidism

Answer 13

cold, dry skin, constipation, slowed heart rate, weight increase, hair loss

Question 14

Why is clinical use of muscarine not recommended?

Answer 14

it can cross the BBB and cause convulsions

Question 15

Methacholine

Answer 15

used to diagnose bronchial hyperreactivity (asthma, COPD) because of its short duration of action

Question 16

What happens when you give methacholine to a patient with bronchiol hyperreactivity?

Answer 16

people suffering from bronchial hyperreactivity will show signs of respiratory insufficiency at a lower dose than healthy individuals

Question 17

What causes glaucoma?

Answer 17

build up of aqueous humor in the iris either due to a decrease in drainage and/or increase in aqueous humor production

Question 18

Open angle glaucoma

Answer 18

clogged or obstructed canal or schlemm, slowly progressing disease typically not apparent until nerve damage of the eye occurs

Question 19

Narrow angle or closed angle glaucoma

Answer 19

drainage blocked by the iris muscles, more acute and severe, can quickly lead to blindness if left untreated

Question 20

treatment of open angle glaucoma

Answer 20

can be treated using M3 muscarinic agonists which will help stretch the trabecular meshwork and reduce clogging

Question 21

M3 treatment of open angle glaucoma relies on what?

Answer 21

muscarinic agonist ability to contract the sphincter muscles

Question 22

Muscarinic agonists used for the treatment of glaucoma

Answer 22

carbachol and pilocarpine

Question 23

Pilocarpine

Answer 23

partial agonist, relieves block of canal of Schlemm, may have less side effects like headache than carbachol

Question 24

Adverse effects of pilocarpine

Answer 24

sweating ,salivation, diarrhea, bronchial mucus secretion, bronchospasms, bradycardia, vasodilation, miosis, impaired night vision, can cross the BBB and cause seizures

Question 25

Bethanechol

Answer 25

used for urinary retention problems and post-operative ileus, orally active (not metabolized quickly), muscarinic selective

Question 26

Cevimeline and pilocarpine

Answer 26

used to treat dry mouth, which is a symptom of Sjogren’s syndrome or a side effect of radiation treatment

Question 27

most well known nicotinic receptor agonist

Answer 27

exogenous nicotine

Question 28

Nicotine as a patch is used for?

Answer 28

smoking cessation

Question 29

Contraindications for nicotine as a drug

Answer 29

cardiovascular issues

Question 30

Varenicline (Chantix)

Answer 30

alpha4beta2 nicotinic receptor partial agonist, activates nicotinic receptor much less than nicotine; blocks nicotine from binding

Question 31

What kind of drugs can reduce intraocular pressure by decreasing formation of aqueous humor rather than by changing the size of the pupil?

Answer 31

Timolol (beta blockers)