2. Cholinergic Drugs

Question 1

Location of M1 receptors

Answer 1

Gastric parietal cells
CNS neurons
Sympathetic postganglionic neurons

Question 2

Location of M2 receptors

Answer 2

Myocardium

Smooth muscles

Question 3

Location of M3 receptors

Answer 3

Glandular tissue

Vessels (smooth muscles and endothelium)

Question 4

Location of nicotinic receptors

Answer 4

Skeletal NMJ
Adrenal medulla
Autonomic ganglia

Question 5

Properties fo direct acting cholinergics

Answer 5

Binds and directly activates receptors
Have affinity and intrinsic activity
Independent of Ach release
Effects similar to endogenous Ach

Question 6

Difference of metacholine from acetylcholine

Answer 6

Methyl substitution on the beta carbon side chain

The methyl group improved selectivity towards muscarinic receptors, and resistance to acetylcholinesterase

Question 7

Difference of carbamic acid esters from acetic acid esterss

Answer 7

Presence of amino group causes resistant to acetylcholinesterase and increased duration of action

Question 8

Properties of carbachol

Answer 8

Non-selective (binds to both muscarinic and nicotinic receptors)

Question 9

Properties of bethanecol

Answer 9

More selective towards muscarinic receptors

Question 10

Enumerate carbamic acid esters

Answer 10

Carbachol

Bethanechol

Question 11

Pilocarpine: state selectivity, type of amine, and other important properties

Answer 11

Selective to muscarinic receptors, antagonized by atropine
Tertiary amine
Only cholinomimetic alkaloid with therapeutic use
Can penetrate the CNS at therapeutic doses

Question 12

Used in the treatment of glaucoma

Answer 12

Carbachol (may also stimulate nicotinic receptors)

Pilocarpine

Question 13

Muscarine: state selectivity, type of amine, and other important properties

Answer 13

Selective to muscarinic receptors, antagonized by atropine
Toxic when ingested and potentially fatal
No therapeutic use
Quaternary amine

Question 14

Heart: state receptors involved and effects of cholinergic drugs

Answer 14

M2 receptors
Decreased HR, rate of conduction, force of contraction of the atrium
Decrease in cardiac output–> decrease in blood pressure

Question 15

Blood vessels: state receptors involved and effects of cholinergic drugs

Answer 15

M3 receptors

Production of NO–> generalized vasodilation

Question 16

GIT smooth muscles: state receptors involved and effects of cholinergic drugs

Answer 16

M3 receptors
increase tone and motility
increase in propulsive movement (ADR: cramps, colicky pain, spasm, nausea, vomiting, diarrhea)
increased intestinal gastric acid secretion

Question 17

Urinary smooth muscles: state receptors involved and effects of cholinergic drugs

Answer 17

M3 receptors
Detrusor muscle contracts, sphincter muscles relax
increased urination

Question 18

Used for GIT atony and urinary retention

Answer 18

Bethanechol

Question 19

Respiratory smooth muscles: state receptors involved and effects of cholinergic drugs

Answer 19

M3 receptors
Bronchospasm
Increased bronchial secretions

Question 20

Eye smooth muscles: state receptors involved and effects of cholinergic drugs

Answer 20

M3 receptors
Contraction of pupillary constrictor muscle and ciliary muscle –> miosis and cyclospasm
Lower IOP in glaucoma

Question 21

Used in the treatment of glaucoma as a miotic agent over carbachol

Answer 21

Pilocarpine; can cross the conjunctival membrane

Question 22

Glandular smooth muscles: state receptors involved and effects of cholinergic drugs

Answer 22

M3 receptors

Outpouring of secretions

Question 23

CNS: state receptors involved and effects of cholinergic drugs

Answer 23

M1 receptor

increase in locomotor activity and improved cognition

Question 24

Taclifenasine properties and indication

Answer 24

M1 selective agonist used in dementia

Question 25

Used for glaucoma

Answer 25

Pilocarpine and carbachol

Question 26

Used for GI disorders (postoperative abdominal distention, gastric atony, adynamic ileus)

Answer 26

Bethanechol | Neostigmine

Question 27

Used for xerostomia

Answer 27

Pilocarpine

Question 28

Used for dementia

Answer 28

Taclifenasine (muscarinic agonist) | Xanomeline

Question 29

Contraindications to the use of direct acting cholinomimetics

Answer 29

``` Asthma Hyperthyroidism Coronary insufficiency Acid peptic disease GIT obstruction ```

Question 30

ADRs of direct acting cholinomimetics

Answer 30

``` Flushing Sweating Salivation Belching Abdominal cramps Urinary bladder tightness Cyclospasm Bronchospasm Hypotension Bradycardia ```

Question 31

Noncovalent acetylcholinesterase inhibitors

Answer 31

Edrophonium | Tacril and Donepezil

Question 32

Edrophonium properties: type of amine, binding, solubility, affinity, indications

Answer 32

Quaternary amine - non-lipid soluble Reversible binding Moderate affinity for AchE, to the anionic site, no covalent bond Only used for diagnosis of myasthenia gravis and Tensilon test

Question 33

Tacrine and Donepezol properties

Answer 33

Inhibits AchE in the CNS, higher affinity Lipid soluble, readily cross the BBB Longer duration of action Treatment of senile dementia of the Alzheimer type

Question 34

Carbamate inhibitors

Answer 34

Site of action: both active sites of AchE, covalent bond Physostigmine (tertiary amine, lipid soluble) Pyridostigmine Neostigmine Rivastigmine Prpoxur

Question 35

Pyridostigmine indication

Answer 35

Chronic management of myasthenia gravis

Question 36

Neostigmine indication and properties

Answer 36

Stimulation of the bladder and GIT Antidote to tubocurarine Symptomatic treatment of MG

Question 37

Rivastigmine indication

Answer 37

Treatment of senile dementia of Alzheimer type

Question 38

Used for senile dementia of Alzheimer type

Answer 38

Rivastigmine Donepezil Tacrine Galantamine

Question 39

used as a miotic agent in highly resistance case of glaucoma

Answer 39

Echothiophate

Question 40

Two active sites for AchE

Answer 40

``` Anionic site (glutamate residue, basic moiety of Ach) Esteratic site (histidine and serine residue) ```

Question 41

Site of action of organophosphates

Answer 41

Esteratic site

Question 42

Given for organophosphate poisoning before aging

Answer 42

Pralidoxime (PAM)

Question 43

Treatment for carbamate posoning

Answer 43

Atropine

Question 44

Used in acute angle closure glaucoma

Answer 44

Physostigmine and Pilocarpine

Question 45

Treatment of myasthenia gravis

Answer 45

Pyridostigmine Abbenomium Neostigmine

Question 46

Difference of myasthenic and cholinergic crisis

Answer 46

Myathenic crisis: due to undermedication; little to no Ach on NMJ Chlonergic crisis: due to overmedication; too much Ach causing neuromuscular block

Question 47

After surgery, in reversing the neuromuscular block, what is administered?

Answer 47

Neostigmine or edrophonium PLUS atropine | To reverse the neuromuscular block without the muscarinic effect

Question 48

Acetic acid esters are abundant in __

Answer 48

NMJ RBC in placent Vascular tissues