Autonomic Pharmacology Introduction

Question 1

What 5 things release ACh?

Answer 1

1. All Motor Neurons
2. All Preganglionic neurons
3. All postganglionic parasympathetic neurons
4. Some Postganglionic sympathetic neurons
5. Some CNS neurons

Question 2

Describe the making of ACh.

Answer 2

Acetyl-CoA + choline = ACh. Reaction via choline acetyltransferase

Question 3

Define cholinergic

Answer 3

Neurotransmission involving ACh

Question 4

Define Nicotinic cholinergic receptors

Answer 4

Receptors in autonomic ganglia and neuromuscular junctions.

Question 5

Define Muscarinic cholinergic receptors.

Answer 5

Receptors on effector organs innervated by cholinergic postganglionic fibers.

Question 6

Discuss ACh transport through a neuron.

Answer 6

1. Choline transported into cell via Sodium dependent choline transporter.
2. Synthesis of ACh from its components
3. ACh transport into storage vesicle via vesicle associated transporter
4. Influx of Calcium causes vesicle fusion with membrane and exocytotic expulsion.
5. Termination of ACh’s action by acetylcholinesterase.

Question 7

What are the MOA’s for Hemicholinum, Vesamicol, and Botulinum toxin?

Answer 7

Hemicholinum: Blocks sodium dependent choline transporter
Vesamicol: Blocks vesicle associated transporter
Botulinum toxin: Prevent docking of ACh containing vesicles and exocytotic release of ACh

Question 8

Where is Norepinephrine released from?

Answer 8

1. Most postganglionic sympathetic neurons.
2. Adrenal medulla
3. Some CNS neurons

Question 9

Define Noradrenergic, adrenergic, and dopaminergic.

Answer 9

Neurotransmission involving norepinerphrine, epinephrine, and dopamine.

Question 10

What is the rate limiting step of the biosynthesis of catecholamines?

Answer 10

Tyrosine hydroxylase

Question 11

Discuss the transport of catecholamines

Answer 11

1. Transport of tyrosine into the nerve ending.
2. Conversion of tyrosine to DOPA via tyrosine hydroxylase
3. Transport of Dopamine into the vesicle via vesicular monoamine transporter
4. Conversion of Dopamine to Norepinephrine via dompamine beta-hydroxylase
5. Influx of Calcium causes release of vesicles
6. Diffusion of NE out of cleft or transport into cytoplasm of terminal via NE transporter.

Question 12

What are the MOAs of Metyrosine, Reserpine and Cocaine?

Answer 12

Metyrosine: Blocks tyrosine hydroxylase
Reserpine: Blocks Vesicular monoamine transporter
Cocaine: Blocks norepinephrine transporter.