ANS Pain

Question 1

Which spinal cord level controls parasympathetic outflow?

Answer 1

craniosacral

Question 2

Which spinal cord level controls sympathetic outflow?

Answer 2

thoracolumbar

Question 3

Where are the preganglionic parasympathetic cell bodies found?

Answer 3

brainstem and sacral spinal cord (S2-S4)

Question 4

Where are the preganglionic sympathetic cell bodies found?

Answer 4

lateral horn of grey matter (VII) in spinal cord; T1-L1/L2

Question 5

Where are the postganglionic parasympathetic cell bodies found?

Answer 5

in autonomic ganglia close to their target organ/gland

Question 6

Where are the postganglionic sympathetic cell bodies found?

Answer 6

paravertebral (sympathetic chain) or prevertebral autonomic ganglia (in abdomen); project to entire body (unlike para.)

Question 7

Which nerves are innervated by the parasympathetic nervous system?

Answer 7

• CN III, oculomotor
• CN VII, facial
• CN IX, glossopharyngeal
• CN X, vagus
• pelvic splanchnic nerves (S2-S4)

Question 8

Is vagus innervation of the stomach afferent or efferent?

Answer 8

both

Question 9

Which organs does the parasympathetic system innervate?

Answer 9

all internal organs of the body, but NONE in body wall (e.g. skin)

Question 10

How does parasympathetic innervation affect the GI tract?

Answer 10

dilate blood vessels leading to GI tract, increasing blood flow and peristalsis

Question 11

How does parasympathetic innervation affect the lens of the eye?

Answer 11

accommodation

Question 12

How does parasympathetic innervation affect the pupils?

Answer 12

constrict

Question 13

How does parasympathetic innervation affect salivary glands?

Answer 13

stimulate secretion

Question 14

How does sympathetic innervation affect the muscles?

Answer 14

dilate vessels for muscles

Question 15

How does sympathetic innervation affect the lungs?

Answer 15

dilate bronchioles –> greater alveolar oxygen exchange

Question 16

How does sympathetic innervation affect heart rate?

Answer 16

increases HR

Question 17

How does sympathetic innervation affect the pupils and ciliary muscles?

Answer 17

dilate pupils and relax ciliary muscles –> more light enters the eye and far vision

Question 18

How does sympathetic innervation affect the GI tract?

Answer 18

divert blood flow away from GI tract, inhibit peristalsis

Question 19

How does sympathetic innervation affect the liver?

Answer 19

glucose secreted from liver

Question 20

Which autonomic motor division causes us to sweat?

Answer 20

sympathetic

Question 21

At which spinal cord levels and for which organs do sympathetic preganglionic neurons synapse in the sympathetic chain?

Answer 21

T1-T5: eye, salivary glands, heart, lung (head to diaphragm/lung

Question 22

At which spinal cord levels and for which organs do sympathetic preganglionic neurons NOT synapse in the sympathetic chain?

Answer 22

T5 - L1/L2: liver, gallbladder, stomach, pancreas, spleen, large intestine, small intestine, adrenal medulla, kidney, urinary bladder, scrotum, penis, ovary, uterus

Question 23

What is the path leading to visceral afferents in visceral referred pain?

Answer 23

celiac trunk (stomach, liver, etc.) –> prevertebral (celiac) ganglia in abdominal aorta –> white ramus communicans –> dorsal root –> spinal cord –> cerebral cortex

Question 24

What is visceral referred pain? What are some examples?

Answer 24

• pain arises from a visceral organ, but the pain is perceived as arising from somatic structures supplied by those same spinal levels
• e.g. MI, appendicitis, cholecystitis, menstrual pain

Question 25

Which spinal nerves does the brain identify pain coming from during a heart attack?

Answer 25

T1-T5 (chest body wall)

Question 26

Which spinal nerves does the brain identify pain coming from during a stomach ulcer?

Answer 26

T7-T9 (epigastric region on body wall)

Question 27

What is somatic referred pain? At what level of the dermatome is the pain detected? Describe how embryological displacement of the diaphragm can lead to somatic referred pain. Where on your body do you feel the pain?

Answer 27

- somatic referred pain is carried by spinal nerves - pain is sharp and easily localized - C3-C5 - inflamed liver/gallbladder can rub against misplaced diaphragm --> pain is referred to C3-C5 dermatome - feel shoulder pain because C3-C5 innervates both diaphragm and shoulder