Cholinesterase Inhibitors and Oximes

Question 1

Discuss how acetylcholinesterase works

Answer 1

Hydrolyzes ACh with a serine residue that does nuclephilic attack-hug, water comes by and rips it all apart and regenerates the enzyme.

This makes these enzymes “serine hydrolases”

Question 2

What ACh Esterase inhibitors are used with Myasthenia Gravis?

Answer 2

Edrophonium, a short lived reversible one, is used to diagnose MG.

The longer lived ones neostigmine and pyridostigmine are used for treating the symptoms.

Question 3

How do we use AChE inhibitors in anesthesia?

Answer 3

Shorter lived reversible AChEs (neostigmine and edrophonium) are used to reverse a non-depolarizing neuromuscular blockade following surgery or other medical procedures.

Question 4

Discuss when and how we use Atropine and 2-PAM

Answer 4

We use these to treat acute anticholinesterase poisoning.

We begin with the antimuscarinic agent atropine to block the muscarinic receptors in glands, bronchioles, bladder, GI tract to reduce the excessive production of saliva and to reduce contractions. If seizures begin, we administer diazepam, however carbamates (atropine) cross the BB barrier poorly, so CNS signs are rare.

2-PAM regenerates the anticholinesterase enzymes.

Question 5

When would we have anticholinesterase inhibitors in the body to worry about?

Answer 5

Nerve agents do this