Cholinergics!

Question 1

Which G-protein coupled muscarinic receptors work through the same pathway as alpha 1?

Answer 1

M1, M3 and M5

Question 2

Which G-protein coupled muscarinic receptors inhibit adenylyl cyclase and reduce cAMP?

Answer 2

M2, M4

Question 3

Location of action for M1, M2, M3, M4, M5, Nm and Nn receptor subtypes.

Answer 3

M1-CNS, stomach
M2- Cardiac muscle, CNS and airway smooth muscle
M3- airway smooth muscle, glandular tissue
M4-CNS
M5- CNS
Nm- skeletal muscle at NMJ
Nn- autonomic ganglia, adrenal medulla CNS

Question 4

Anti-muscarinic drugs competitively antagonize ACh where?

Answer 4

at muscarinic receptors only.

Question 5

What is the more detailed MOA of antimuscarinic drugs?

Answer 5

Cation potion of the drug fits into Ach’s place on the cholinergic receptor and reversibly inhibits Ach binding.

Question 6

What kind of responses do antimuscarinic drus allow to predominate?

Answer 6

Sympathetic.

Question 7

How is the competitive inhibition of antimuscarinic drugs reversed?

Answer 7

If the ACh concentration is increased.

Question 8

Structurally why do we care about atropine and scopalamine?

Answer 8

They are tertiary amines- alkaloids of the belladonna plants which CAN cross the BBB.

Question 9

Structurally why do we care about gycopyrrolate/Robinal?

Answer 9

It is a quaternary ammonium derivative that CANNOT cross the BBB.