Lecture 08_Fall

Question 1

The Autonomic Nervous System regulates ___, ____, ___, and ___ function.

Answer 1

cardiac muscle, smooth muscle, visceral and gland function

Question 2

What are the two divisions of the ANS?

Answer 2

Smypathetic Nervous System (the adrenergic system) and Parasympathetic Nervous System (the cholinergic system)

Question 3

Which nerve transmits sensory input from the thoracic and abdominal organs?

Answer 3

the vagus nerve (CN X)

Question 4

Most actions of the ANS are ______.

Answer 4

Involuntary

Question 5

List the 8 things regulated by the ANS

Answer 5

HR, BP, GI system, temp, hunger, thirst, osmolarity, gland secretions

Question 6

The peripheral ANS is the _____ component of the system.

Answer 6

Efferent (motor)

Question 7

How do neurons of the Peripheral ANS differ from somatic neurons?

Answer 7

Autonomic: two-neuron unit
-1st neuron from CNS –> ganglion (myelinated) -2nd neuron from ganglion –> target organ (unmyelinated)

Somatic: single myelinated axon with cell body in spinal cord

Question 8

T or F. Both SNS and PNS are tonically active?

Answer 8

True. They have baseline activity that can increase or decrease - More than one way to accomplish an effect with precision

Question 9

Which system is the “FIGHT OR FLIGHT” system?

Answer 9

Sympathetic Nervous System (SNS) = Adrenergic like adrenaline = “FIGHT OR FLIGHT”

Question 10

Which system is know as the “REST & DIGEST” system?

Answer 10

Parasympathetic Nervous System (PNS) = Cholinergic = “REST & DIGEST”

Question 11

Which system is also known as the cranio-sacral system? Why?

Answer 11

PNS because the pre-ganglionic neurons originate in brainstem or sacral segments of spinal cord

Question 12

What is the Ratio of pre- : post-ganglionic fibers in the SNS?

Answer 12

1:20 - Post-ganglionic fibers originate in sympathetic ganglion –> effector tissues - they travel within spinal nerves and outnumber pre-ganglionic fibers by 20-30:1

This allows for concurrent stimulation of many organs at once (mass sympathetic discharge)

Question 13

Which system is also known as thoraco-lumbar system? Why?

Answer 13

SNS because their pre-ganglionic fibers originate from spinal cord at T1–L3

Question 14

What are the 3 endogenous catecholamines?

Answer 14

Epi, NE, and Dopamine

Question 15

Adrenal stimulation leads to release of what 2 catecholamines?

Answer 15

Epi (80%) and NE (20%)

Question 16

Which catecholamine acts as a CNS neurotransmitter?

Answer 16

Dopamine

Question 17

_____ is synthesized & stored in the adrenal medulla but ___ is synthesized & stored in the adrenal medulla AND post-ganglionic neurons

Answer 17

Epi, NE

Question 18

Do systemic catecholamines cross the BBB?

Answer 18

No

Question 19

What are sympathomimetics?

Answer 19

Drugs that act like catecholamines but have a different structure

Question 20

Almost all endogenous ___ undergoes re-uptake into the pre-synaptic terminal and can then be metabolized by ____.

Answer 20

NE, Monoamine oxidase (MAO)

Question 21

Where are circulating catecholamines (NE + Epi) metabolized?

Answer 21

in the liver and kidney

Question 22

What metabolizes circulating catecholamines in the liver and kidneys? What is the metabolite?

Answer 22

Catechol-O-methyltransferase (COMT), Metabolite is vanillylmandelic acid

Question 23

What is used in the diagnosis of a pheochromocytoma?

Answer 23

vanillylmandelic acid

Question 24

What is the rate limiting step in the synthesis of Epi shown below? What effect does NE have at that point?

Phenylalanine -> Tyrosine −*-> DOPA -> DA -> NE -> Epi

Answer 24

*Tyrosine hydroxylase = rate-limiting step

NE causes negative feedback at this point

Question 25

Which catecholamine is released at the effector tissues in the PNS?

Answer 25

Ach

Question 26

What are the two types of cholinergic receptors?

Answer 26

Nicotinic and Muscarinic

Question 27

Where are nicotinic receptors located at?

Answer 27

On cell bodies of all post-ganglionic neurons, within ganglia of both SNS and PNS Neuromuscular junction also has n-ACh-R - Blocked by non-depolarizing neuromuscular blocking agents

Question 28

Where are muscarinic receptors found?

Answer 28

On cell membranes of effector tissues - also on pre-synaptic membrane of sympathetic (SNS) nerve terminals ( Stimulation ->
inhibits release of NE)

Question 29

____ is a prototype muscarinic blocker
-> sympathomimetic activity

Answer 29

Atropine

Question 30

____ is the first choice for bradyarrhythmias

Answer 30

atropine

Question 31

T or F. Atropine can cross the BBB.

Answer 31

TRUE

Question 32

Where do the pre-ganglionic neurons originate for the PNS?

Answer 32

Pre-ganglionic neurons originate in brainstem or sacral segments (S2-S4) of spinal cord which is why it is also known as cranio-sacral system

Question 33

___ and ___ inhibit NE re-uptake and lead to high levels of NE.

Answer 33

TCAs and Cocaine

Question 34

Post-ganglionic fibers of the SNS release __ at the effector tissue, except for at sweat glands where ___ is released and the adrenal medulla where both ___ and ___ are released.

Answer 34

NE, Ach, NE and Epi

Question 35

Cholinergic antagonists competitively bind to ___ receptor and block activation by ___.

Answer 35

muscarinic, Ach

Question 36

Which of the following does not have a tertiary amine structure? A. Atropine B. Scapolamine C. Glycopyrrolate

Answer 36

C. Glyco is a quarternary ammonium

Question 37

Which of the following should be used with caution in patients with closed-angle glaucoma? A. Atropine B. Scapolamine C. Glycopyrrolate

Answer 37

B. Scapolamine

Question 38

Which of the following should be used with caution in patients that have narrow-angle glaucoma? A. Atropine B. Scapolamine C. Glycopyrrolate

Answer 38

A. Atropine

Question 39

Which of the following should be used with caution in patients that have BPH? A. Atropine B. Scapolamine C. Glycopyrrolate

Answer 39

A. Atropine

Question 40

What should be used to treat central anticholinergic syndrome that is associated with atropine?

Answer 40

Physostigmine

Question 41

T or F. B1 adrenergic receptors have equal affinity for Epi and NE.

Answer 41

True

Question 42

Stimulation of ___ inhibits the release of NE and reduces the sympathetic outflow, causes vasodilation and sedation

Answer 42

pre-synaptic A2 adrenergic receptors

Question 43

Stimulation of ___ adrenergic receptor causes vasodilation, bronchodilation, renal vessel relaxation

Answer 43

B2

Question 44

___ adrenergic receptors are responsible for renal perfusion and diuresis.

Answer 44

DA

Question 45

T or F. Patients that undergo a heart transplant will no longer have parasympathetic innervation to the heart and lack vagal tone.

Answer 45

True

Question 46

T or F. Patients that undergo a heart transplant will lack the normal tachycardia and contractility response to hypovolemia and hypotension, but will still respond to increased BP with reflex bradycardia. .

Answer 46

False. They will be unable to respond to hypotension or hypertension with a change in heart rate or contractility.

Question 47

How do you maintain hemodynamic stability in patients that have had a heart transplant?

Answer 47

Need to have adequate intravascular volume Treat bradycardia with agents that directly affect the heart - Isoproterenol and glucagon are commonly used