Autonomic Drugs

Question 1

The motor (efferent) portion of the nervous system can be divided into two subdivision (2):

Which if these is largely independent?

Which is largely concerned with consciously controlled function?

Answer 1

• Autonomic and Somatic
• Autonomic
• Somatic

Question 2

Anatomy of the autonomic nervous system

1. What is the 3rd division of the ANS?
2. Where is it found?
3. What are the 2 neuronal networks that receive preganglionic fibers from the parasympathetic system and postganglionic sympathetic axons?

Answer 2

1. Enteric Nervous System
2. Located in the walls of the gastrointestinal system

3. Myenteric Plexus (Auerbach)
    Submucous Plexus (Meissner)

Question 3

If ANS fiber is called cholinergic, what does it synthesize and release?

Answer 3

Acetylcholine

Question 4

True or false.

All efferent fibers leaving the CNS release acetylcholine.

Answer 4

True

Question 5

Most postganglionic sympathetic fibers release what?

What is the other name?

Answer 5

• Norepinephrine

- Adrenergic Fibers

Question 6

Indicate if Parasympathetic or Sympathetic and name what neurotransmitter does the postganglionic fiber releases.
A. Renal vasculAr smooth muscle
B. Sweat glands
C. Cardiac and smooth muscles, gland cell, and nerve terminals
D. Skeletal Muscle

Answer 6

A. Sympathetic: Dopamine
B. Sympathetic: Acetylcholine (Muscarinic)
C. Sympathetic: Acetylcholine (M)
     Parasympathetic: NE
D. Somatic: Acetylcholine

Question 7

Acetylcholine is synthesized in?
From what component?
And through action of what enzyme?

Answer 7

• Cytoplasm
• Acetyl-CoA and Choline
• Choline Acetyltransferase

Question 8

Acetyl-CoA is synthesized in?

Answer 8

Mitochondria

Question 9

What does botulinum toxin do to acetylcholine vesicle?

Answer 9

Block! Through enzymatic removal of 2 amino acids from one of more of the fusion proteins

Question 10

NE is converted to Epinephrine in what location?

Answer 10

Adrenal Medulla

Question 11

Rate-limiting step in catecholamine transmitter synthesis?

This can be inhibited by?

Answer 11

• Tyrosine to Dopamine

- Metyrosine (Tyrosine Analog)

Question 12

Cocaine and Tricyclic Antidepressant drugs effect on transmitter activity?

Answer 12

Increase transmitter activity in the synaptic cleft.
NET carries NE and similar molecules back into the cell cytoplasm from synaptic cleft.
Cocain and TCAs inhibit NET, thus, termination of synaptic activity will be blocked. (NET is partially responsible for the termination of synaptic activity.)

Question 13

• It is a neurotoxin that can cause release of transmitter (subs P) from neurons.
• If given in high doses will cause?

Answer 13

• Capsaicin

- Destruction of neurons

Question 14

The primary effect of muscarinic (a.k.a anticholinergic: atropine) agonist on cardiovascular system?

Answer 14

Reduction of PVR and changes in heart rate

Question 15

IV infusions on ACh in human:

• Minimal doses of 20-25mcg/min causes?
• Larger doses produce?

Answer 15

• Vasodilation resulting in reduction in BP and reflex increase in HR
• Bradycardia and decrease AV node conduction velocity in addition to hypotension

Question 16

Effect of cholinoceptor stimulants (ACh) in the following:
A. Ciliary Muscle
B. SA node
C. Arteries and Vein
D. Bronchial Glands
E. Glands

Answer 16

A. Contraction (Miosis)
B. Decrease in rate
C. Dilation
     Constriction (in high-doses)
D. Stimulation
E. Secretion