AChE inhibitors

Question 1

what are the 2 mechanisms of inhibition?

Answer 1

1. non-covalent competitive inhibition (inhibitors competes with ACh)
2. covalent inactivation of AChE - longer duration of effect because longer half life; inhibitor modifies AChE to generate: carbamylated AChE and phosphorylated AChE

Question 2

edrophonium

Answer 2

competitive inhibition
2 - 10 minute block
used to distinguish myasthenic vs. cholinergic crisis

Question 3

ambenonium

Answer 3

• may have mixed covalent/non-covalent activity
• 4 - 8 hour block
• used to treat myasthenia gravis

Question 4

physiostigmine

Answer 4

• carbamylated covalent AChE inhibitors
• 0.5 - 6 hour block
• isolated from plant
• tertiary amine (CNS effects)
• used to treat glaucoma

Question 5

neostigmine

Answer 5

• synthetic, quarternary amine
• carbamylated covalent inhibitor
• used to treat myasthenia and to stimulate GI and urinary tract

Question 6

pyridostigmine

Answer 6

similar to neostigmine

Question 7

echothiophate

Answer 7

• used to treat glaucoma

- phosphorylated (irreversible) inhibitor (+100 hr block)

Question 8

isoflurophate

Answer 8

• glaucoma treatment

- phosphorylated (irreversible) inhibitor (+100 hr block)