Cholinergic Agonists- T1

Question 1

The three classes of muscarinic agonists and examples

Answer 1

1. Ach derivatives: Ach, carbachol, bethanachol, methacholine
2. alkaloids: pilocarpine
3. synthetic- cevimeline

Question 2

example of nicotinic agonist drug

Answer 2

chantix

Question 3

cholinergic agonists have predominant actions on:

Answer 3

1. autonomic effector organs innervated by postganglionic parasympathetic nerves
2. cells containing cholinergic receptors.

Question 4

cholinergic agonists primarily divided into:

Answer 4

1. Ach and synthetic choline esters

2. cholinomimetic natural alkaloids and analogs.

Question 5

cholinergic agonists also activate__ found in

Answer 5

nicotinic receptors found in the ganglia, neuromuscular junction and CNS

Question 6

Describe Ach

Answer 6

• endogenous NT; no selectivity for muscarinic vs. nicotinic receptors
• rapid metabolism by Achesterase
• Ach is a (+) polar molecule, ester, that undergoes hydrolysis–> carboxylic acid and an alcohol.

Question 7

derivatives of choline esters are generally

Answer 7

generally more resistant to AChE metabolism and have altered cholinergic receptor selectivity.

Question 8

give the susceptibility to cholinesterase metabolism

Answer 8

Ach>methacholine> carbachol> bethanechol

Question 9

activation of specific muscarinic receptors in various organs. (10)

Answer 9

decreases heart rate, vasodilation, increase intestinal smooth muscle contraction, motility, urinary( increased detrusor muscle contraction), increase bronchial constriction, increased salivation, increased salivation, increased mitosis, increased accommodation for near vision

Question 10

What determines Gs/GI, GQ for signal transaction of muscarinic receptors

Answer 10

alpha subunit

Question 11

all receptors coupled to phosphoionsitide are

Answer 11

GQ

Question 12

coupling of muscarinic receptors to effectors via GO/I

Answer 12

• M2 receptor activation results in decreased heart rate and decreased neurotransmitter release from cholinergic nerves.
• M2 receptors regulate cAMP by decreasing adenylyl cyclase activity. cAMP regulates heart rate and contractility.

Question 13

beta receptor–>

Answer 13

Q activity of cardiac myocytes, also activate potassium channels, stimulating the depolarization of cardiac cells.

Question 14

what drug(s) can produce mitosis during eye surgery and decrease intraocular pressure

Answer 14

Ach and carbachol. pupil constriction via M3 receptors.

Question 15

what drug for airway hyperactivity test

Answer 15

methacholine–> causes constriction and increased resistance to airflow.

Question 16

what drug for urinary urgency and increase GI motility

Answer 16

bethanechol. bethanechol increases tension on the bladder.

Question 17

cholinergic agonist natural alkaloids are

Answer 17

more selective for muscarinic vs nicotinic receptors, pilocarpine is the only one of therapeutic value, and tend to give long duration of action.

Question 18

pilocarpine cardiovascular effects

Answer 18

decreases heart rate and blood pressure

Question 19

alkaloids smooth muscle effects

Answer 19

pupillary constriction, initial increase followed by a decreased intraocular pressure, decreased far vision, increase bronchial and GI muscle contraction, promote urination.

Question 20

alkaloids exocrine gland effects

Answer 20

sweating, N/V, salivation, lacrimation.

Question 21

therapeutic use of pilocarpine

Answer 21

glaucoma

Question 22

describe chant and what type of drug it is

Answer 22

nicotinic agonist.

• partial agonist of the alpha2beta4 neuronal nicotinic receptor.
• activates the receptor at sub-threshold levels but prevents binding of nicotine.

Question 23

why does chant work for stopping smoking?

Answer 23

it you give an antagonist, you would get full blown nicotine withdrawal. but since chantix is a partial agonist it has a dual effect: antagonistic and partial agonist.