Cholinergic Drugs

Front 1

Hemicholinium

Back 1

Blocks the uptake of choline into the neuron (both from reuptake after ACh breakdown and from diet)

Front 2

Vesamincol

Back 2

Prevention of packaging ACh into synaptic-destined vesicles (similar to Reserpine in the Adrenergic system).

Note that choline is conjugated with Acetyl Co-A in the cytoplasm of the neuron before packaging.

Front 3

Latrotoxin,Botulism Toxin, Mg++

Back 3

All responsible for inhibiting fusion of the ACh-containing vesicles with the presynaptic membrane, thereby preventing release of ACh.

Front 4

Tubocurare (curare)

Back 4

Neuro-muscular blocker. Binds as a non-depolarizing antagonist to the post-synaptic receptors in the Cholinergic system. (muscle-relaxant)

Front 5

Suxamethonium (succinylcholine)

Back 5

Neuro-muscular blocker. Binds as a reversible agonist to the post-synaptic receptors in the Cholinergic system. Causes initial depolarization and subsequent inhibition of subsequent depolarization. Muscle relaxant used for intubation.

NOTE: There is no such thing as a perfect drug. Sux acts on primarily nicotinic, but also muscarinic, receptors. Leads to bradycardia, dysrhythmias, and raised intraocular pressure.

Front 6

Reversible Anticholinesterases
Name one

Back 6

Increases ACh in synapse. Carbamates. End with "-stigmine"
physostigmine, neostigmine, pyridostigmine

Front 7

Trimethophan

Back 7

A direct ganglionic blocker: nicotinic antagonist. Used in hypertensive crisis.
(decreases muscle and neuron excitability; therefore getting decreased motility and decreased vascular tone)

Front 8

Atropine

Back 8

Muscarinic receptor antagonist

Front 9

Edrophonium

Back 9

A reversible Anticholinesterase. Used in the diagnosis of Myasthenia Gravis.

Front 10

Parathion

Back 10

Irreversible Anticholinesterase. Insectiside (along with Malathion and Chlorpyifos)

Front 11

Soman

Back 11

Irreversible Anticholinesterase. Biological warfare agent.

Front 12

Echothiophate

Back 12

Irreversible anticholenesterase. Treatment of glaucoma.

Front 13

Anticholenesterase mechanism

Back 13

Agents bind to the serine subunit of AChesterase. Reversible agents disassociate, whereas irreversible agents have a strong affinity and poison the enzyme.

Front 14

Pralidoxime (2-PAM)

Back 14

Reactivator of ACh-esterase. Must be administered to patient within 2 hours of exposure to irreversible anticholenesterase.

Front 15

Mechanism of Odd-Numbered Muscarinic Receptors

Back 15

A G-protein Coupled receptor.

Acts through Gq to activate PLC and release DAG and IP3. Increases Ca++

Front 16

Mechanism of Even-Numbered Muscarinic Receptors

Back 16

A G-Protein Coupled Receptor.

Acts through Gi to turn off adenylyl cyclase, which decreases cAMP, thereby reducing cellular activation.

Front 17

Muscarinic Receptors
Characteristics

Back 17

GPCR's
M1-M5 (5 localizations/types)
3rd intracellular loop conveys specificity

Front 18

Nicotinic Receptor
Characteristics

Back 18

Pentameric (5 subunit) structure
2 alpha subunits -site of ACh binding
1 beta, 1 gamma, 1 delta or epsilon
2x Ach binding --> conformational change

Front 19

Acetylcholine

Back 19

Muscarinic Agonist

Front 20

Carbachol

Back 20

Muscarinic Agonist

Front 21

Bethanechol

Back 21

Muscarinic Agonist. Promotes voiding in people with neurogenic bladders.

Front 22

Muscarine

Back 22

Muscarinic Agonist

Front 23

Pilocarpine

Back 23

Muscarinic Agonist. Useful in Glaucoma

Front 24

Atropine

Back 24

Muscarinic Antagonist

Front 25

Scopolamine

Back 25

Muscarinic Antagonist. Good for motion sickness. Also good pre-operatively in reducing GI motility and secretion.

Front 26

Muscarinic antagonist effect on bladder

Back 26

Used in cystitis to decrease urgency

Front 27

Muscarinic antagonist effect on Vessels

Back 27

"atropine flush"

Front 28

Muscarinic antagonist effect on GI

Back 28

Decreased motility and acid secretion. Used in peptic ulcer disease.

Front 29

Muscarinic antagonist effect on Sweat

Back 29

decreased sweat, increase temperature

Front 30

Organophosphate Poisoning

Back 30

Cholinergic Toxidrome. Treat with Atropine and PAM-2

Front 31

Muscarine poisoning (mushrooms)

Back 31

Cholinergic Toxidrome. Treat with atropine only. (no PAM-2)

Front 32

Atropine Poisoning

Back 32

Rare. Anticholineregic Toxidrome. Red, Hot, Mad, Dry, Blind, Seizing.

Treat: AChE inhibitor (physostigmine) because ACh is being blocked by atropine.