cholinergic agent

Question 1

acetylcholine has a higher affinity for the ______ receptor than the ______ receptor

Answer 1

muscarinic
nicotinic

Question 2

choline is transported into the presynaptic nerve terminal by a _____

Answer 2

-sodium-dependent choline transporter (CHT)
-this transporter can be inhibited by hemicholinium

Question 3

ACh is synthesized from choline and acetyl- CoA by the enzyme

Answer 3

-choline acetyltransferase (ChAT)

Question 4

ACh is then transported into the storage vesicle by a second carrier, the ________ this can be inhibited by ______

Answer 4

-vesicle-associated transporter (VAT)
-vesamicol

Question 5

Release of transmitter occurs when an action potential opens__________ and increases the intracellular____. Fusion of vesicles with the surface membrane results in release of ACh. This step can be blocked by ______

Answer 5

-voltage sensitive calcium channel
-calcium
-botulinum toxin (botox)

Question 6

ACh binds to _____ on the postsynaptic cell

Answer 6

cholinoceptors

Question 7

ACh ‘s actions is terminated by metabolism by the enzyme ______

Answer 7

acetylcholinesterase (AChE)

Question 8

parasympathmimetic actions (agonists)

Answer 8

-direct agonist: activates cholinoceptors
-indirect agonist: stimulate acetylcholine release, inhibit acetylcholinesterase (AChE) for ACh degradation

Question 9

parasympatholytic actions (antagonists)

Answer 9

direct or indirect
-many drugs exhibit anticholinergic side-effect

Question 10

muscarinic agonist effect on the heart

Answer 10

M2 activation leads to decrease in HR, conduction and force (bradycardia)

Question 11

Muscarinic agonist effects on the endocrine glands

Answer 11

M3 increase secretion of lachrymal, tracheobronchial, salivary, digestive, sweat glands

Question 12

muscarinic agonist effect on the smooth muscles

Answer 12

M3 increases contraction (M2 inhibit relaxation)

Question 12

muscarinic agonist effect on sphincters

Answer 12

M3 relaxation

Question 13

muscarinic agonist effect on CNS

Answer 13

-not all muscarinic agonist able to access CNS
-CNS effects mainly mediated by M1 receptors
-produce tremor, hypothermia, increased locomotor activity, improved cognition

Question 14

cholinoceptors agonist (muscarinic agonist)

Answer 14

acetylcholine
methacholine
carbachol
bethanecol
muscarine
pilocarpine

Question 15

muscarinic agonist (mushroom poisoning) PSNS

Answer 15

-bradycardia
-nausea, cramps, vomiting, diarrhea
-bronchoconstriction
-salivation
-visual disturbances

Question 16

muscarinic agonist (mushroom poisoning) SNS

Answer 16

sweating
-hypotension: uninnervated muscarinic receptors in blood vessel endothelium cells mediating vasodilation via NO

Question 17

xerostomia

Answer 17

-dry mouth, cottonmouth
-pilocarpine is used for the treatment of xerostomia that
follows head and neck radiation treatments (M3 receptor)

Question 17

pilocarpine hypofunction of salivary glands

Answer 17

xerostomia and sjogren syndrome

Question 18

sjogren’s syndrome

Answer 18

-an autoimmune disorder occurring primarily in women
-secretions from the salivary glands are reduced
Pilocarpine is useful in increasing secretions

Question 19

clinical use of pilocarpine

Answer 19

open-angle glaucoma; dry mouth due to hypofunction of salivary
glands e.g. Sjogren’s or cancer radiotherapy (“xerostomia”)

Question 20

clinical use of methacholine

Answer 20

Provocative test for hyperreactive airways

Question 20

clinical use of bethanechol

Answer 20

GI stimulation or treatment of urinary retention

Question 21

clinical use of carbachol

Answer 21

ocular (surgery, glaucoma)

Question 22

muscarinic receptor agonist side effects

Answer 22

-PSNS effects such as DUMBBELS
-SNS effects sweating
-Use with caution in patients with asthma, coronary insufficiency, or peptic ulcer
-Cardiovascular
-Respiratory