Lecture 24: Autonomic Nervous System

Question 1

Which ANS neurons have cell bodies located within the CNS, myelinated axons, and use ACh as their primary neurotransmitter?

Answer 1

Preganglionic neurons

Question 2

Which ANS neurons have cell bodies located in peripheral ganglia, unmyelinated axons, and use ACh as their neurotransmitter for parasympathetics/Norepinephrine as their neurotransmitter in sympathetics?

Answer 2

Postganglionic neurons

Question 3

How many pairs of ganglia are included in the thoracic sympathetic chain?

Answer 3

12 pairs of ganglia and the superior/middle/inferior cervical ganglia

Question 4

How do nerves in the thoracic sympathetic chain exit to enter the thorax?

Answer 4

As cardiopulmonary splanchnic nerves

Question 5

What are the functions of cardiopulmonary splanchnic nerves?

Answer 5

Coronary artery dilation, increase heart rate, bronchodilation

Question 6

What do splanchnic nerves supply and where do they synapse?

Answer 6

Supply abdominal viscera and synapse in prevertebral ganglia

Question 7

Greater splanchnic nerves

Answer 7

Supply T5-T9; synapse in celiac ganglion

Question 8

Lesser splanchnic nerves

Answer 8

Supply T10-T11; synapse in superior mesenteric ganglion

Question 9

Least splanchnic nerve

Answer 9

Supply T12; synapse in aorticorenal ganglion

Question 10

What is the role of circulating norepinephrine?

Answer 10

Constricts blood vessels (raises arterial pressure due to great effect on skeletal muscles), increase heart activity, inhibits GI tract, dilates pupil

Question 11

What is the role of circulating epinephrine?

Answer 11

Increases cardiac output, affects metabolism

Question 12

What is the stress response?

Answer 12

Mass discharge of entire sympathetic system leading to increased arterial pressure, increased metabolism, increased glycolysis, etc.

Question 13

Which cranial nerve contains 75% of all parasympathetic fibers?

Answer 13

Vagus nerve (CN X)

Question 14

Which cranial nerves carry parasympathetic signals?

Answer 14

Oculomotor (CN III), Facial (CN VII), Glossopharyngeal (CN IX), Vagus (X)

Question 15

What structures does the oculomotor nerve innervate?

Answer 15

Four of the six extrinsic eye muscles and levator palpebrae superioris

Question 16

What structures does the facial nerve innervate?

Answer 16

Primary motor to muscles of facial expression, sensation of taste from anterior 2/3 of the tongue

Question 17

What structures does the glossopharyngeal nerve innervate?

Answer 17

General sensation/sensation of taste from posterior 1/3 of tongue

Question 18

Where do the postganglionic fibers of the glossopharyngeal nerve terminate?

A. Lacrimal gland
B. Ciliary ganglion
C. Otic ganglion
D. Parotid gland

Answer 18

D. Parotid gland

Question 19

What structures does the vagus nerve innervate?

Answer 19

Motor to muscles of 4th, 5th pharyngeal arches (swallowing, speech)

Question 20

List branches of the vagus nerve. What does vagus nerve become after piercing diaphragm?

Answer 20

Cardiac branches, pulmonary branches, esophageal branches, left/right recurrent laryngeal nerves; becomes gastric nerve

Question 21

What molecules make up acetylcholine?

Answer 21

Choline, Acetyl-CoA

Question 22

What enzyme breaks down acetylcholine?

Answer 22

Acetylcholinesterase

Question 23

What neurotransmitter is derived from tyrosine and dopamine?

Answer 23

Norepinephrine

Question 24

How is norepinephrine removed?

Answer 24

Destroyed by monamine oxidase or COMT

Question 25

Where are muscarinic receptors for ACh found?

Answer 25

On all effector cells stimulated by postganglionic cholinergic neurons

Question 26

Where are nicotinic receptors for ACh found?

Answer 26

Autonomic ganglia at synapses between preganglionic and postganglionic neurons; present in neuromuscular junctions of skeletal muscles

Question 27

What types of functions are alpha adrenergic receptors associated with?

Answer 27

Vasoconstriction, iris dilation, intestinal relaxation, bladder sphincter contraction, inhibition of neurotransmitter release, etc.

Question 28

What types of functions are beta1 adrenergic receptors associated with?

Answer 28

Cardioacceleration, increased myocardial strength, lipolysis

Question 29

What types of functions are beta2 adrenergic receptors associated with?

Answer 29

Vasodilation, intestinal relaxation, uterine relaxation, calorigenesis, glycogenolysis, relaxation of bladder wall

Question 30

Which of the following adrenergic receptors is associated with thermogenesis? A. alpha 2 B. beta 2 C. beta 3 D. muscarinic

Answer 30

C. beta 3

Question 31

Norepinephrine, epinephrine, methoxamine, albuterol are all examples of what type of drug?

Answer 31

Sympathomimetic

Question 32

Which drugs cause the release of norepinephrine?

Answer 32

Ephedrine, tyramine, amphetamine

Question 33

Which drug has an anti-hypertensive effect by blocking the release of norepinephrine? A. Amphetamine B. Propranolol C. Albuterol D. Guanethidine

Answer 33

D. Guanethidine

Question 34

Which drug blocks synthesis and storage of norepinephrine?

Answer 34

Reserpine

Question 35

Which drug blocks sympathetic alpha receptors?

Answer 35

Phenoxybenzamine/phentolamine

Question 36

Which drug blocks sympathetic beta1 and beta2 receptors?

Answer 36

Propranolol

Question 37

Which drug blocks sympathetic beta1 receptors?

Answer 37

Metoprolol

Question 38

Which drug blocks transmission through autonomic ganglia?

Answer 38

Hexamethonium

Question 39

Which drugs inhibit acetylcholinesterase, acting on cholinergic effector organs?

Answer 39

Neostigmine, pyridostigmine, ambenonium

Question 40

Which drugs block cholinergic activity?

Answer 40

Atropine, homatropine, scopolamine

Question 41

What are the general sympathetic and parasympathetic effects on the eyes?

Answer 41

Sympathetic: Pupil dilation Parasympathetic: pupil constriction, lens focusing

Question 42

What are the general sympathetic and parasympathetic effects on glands?

Answer 42

Sympathetic: secretion of sweat (cholinergic mostly) Parasympathetic: stimualtion of lacrial, nasal, salivary, upper GI glands

Question 43

What are the general sympathetic and parasympathetic effects on the GI tract?

Answer 43

Sympathetic: inhibition of peristalsis Parasympathetic: promotes peristalsis, relaxes sphincters

Question 44

What are the general sympathetic and parasympathetic effects on the heart?

Answer 44

Sympathetic: increases heart rate, contraction strength Parasympathetic: decreases heart rate, contraction strength

Question 45

What are the general sympathetic and parasympathetic effects on the systemic blood vessels?

Answer 45

Sympathetic: constricts blood vessels Parasympathetic: no effect

Question 46

What are the general sympathetic and parasympathetic effects on arterial pressure?

Answer 46

Sympathetic: acute increase Parasympathetic: little effect

Question 47

What are the general sympathetic and parasympathetic effects on the body?

Answer 47

Sympathetic: inhibition of endodermal structures Parasympathetic: excitation of endodermal structures