ANS

Question 1

Explain Cholinomimetic Drug strategies

Answer 1

Cholinomimetic drugs are those that mimic Acetylcholine by directly or indirectly activating ACh receptors.

Direct: Agents combine w/ Cholinoceptor in that same way as ACh.

Indirect: Agents are Cholinesterase inhibitors which results in prolongs the action of ACh on the post-synaptic membrane

Question 2

Where are Nicotinic Receptors?

Where are Muscarinic Receptors?

Answer 2

Nicotinic ACh-Receptors:

• Adrenal Medulla (Sympathetic)
• Sympathetic Chain Ganglia
• Parasympathetic Ganglia
• Striated muscle (Somatic Motor) (Cardiac & Skeletal)

Muscarinic ACh-Receptors:

• Effector Organs innervated by Parasympathetic Postganglionic n.

Question 3

Compare & Contrast Muscarinic & Nicotinic Receptors

Answer 3

Nicotinic:

• 5 subunit Ligand-Gated Na+ channel
• Excitatory only: ACh & Nicotine
• Antagonists: Curare (NM only)

Muscarinic:

• GPCR with Mixed Excitatory or Inhibitory function
• Agonists: ACh Muscarine
• Antagonists: Atropine

Question 4

Sympathetic Stimulation

Answer 4

Adrenal Medulla: Epinephrine Secretion

Arteries: Vasoconstriction (except Coronary & skeletal m. a, which are dilated)

Heart: Increased HR & AV conduction; Increased Contractility

GI: Decreased motility & secretions

Respiratory: Bronchodilation

Urinary: Bladder relaxation; Sphincter contraction

Eye: Pupil Dilation (Mydriasis)

Question 5

Parasympathetic Stimulation

Answer 5

Adrenal Medulla: -

Arteries: -

Heart: Decreased HR & AV conduction; Slight decrease in Contractility

GI: Increased motility & secretions

Respiratory: Bronchoconstriction

Urinary: Bladder Contraction; Sphincter Relaxation

Eye: Pupil constriction (Miosis)

Question 6

Anticholinergic drug types

Answer 6

Anticholinergic drugs:

Antimuscarinic:

• Non selective (Atropine)
• M1-Selective

Antinicotinic:

• Ganglion blockers
• Neuromuscular blockers (Tubocurarine)

Cholinesterase Regenerators: (Pralidoxime)