2.4 Nerve Supply to Abdominal Viscera

Question 1

What are the 3 sympathetic nerves which supply the abdominal viscera?

Answer 1

1. Abdominopelvic splanchnic nerves (greater, lesser & least)
2. Prevertebral sympathetic ganglia
3. Abdominal aortic plexuses

Question 2

What are the 2 parasympathetic nerves which supply the abdominal viscera?

Answer 2

1. Anterior & posterior vagal trunks (vagus nerve - 10th cranial nerve)
2. Pelvic splanchnic nerves (S2, S3 & S4)

Question 3

What happens to GI secretion under parasympathetic innervation?

Answer 3

Increased

Question 4

What happens to GI secretion under sympathetic innervation?

Answer 4

Decreased

Question 5

What happens to peristalsis/GI motility under parasympathetic innervation?

Answer 5

Increased

Question 6

What happens to peristalsis/GI motility under sympathetic innervation?

Answer 6

Decreased

Question 7

What happens to blood vessels under parasympathetic innervation?

Answer 7

Vasodilation

Question 8

What happens to blood vessels under sympathetic innervation?

Answer 8

Vasoconstriction

Question 9

What is the effect of vagotomy (cutting of one or more branches the vagus nerve) on gastric secretion?

Answer 9

Permanent reduction

Question 10

What is the functional difference between the greater, lesser and least abdominopelvic splanchnic nerves, and the pelvic splanchnic nerves? (splanchnic means viscera)

Answer 10

Abdominopelvic provide sympathetic innervation, while pelvic provide parasympathetic innervation

Question 11

What is the chief difference in the arrangement of ganglia in the sympathetic & parasympathetic nervous systems?

Answer 11

Sympathetic tend to be close to the vertebrae (sympathetic chain) = short pre-ganglionic fibres & long post-ganglionic fibres; parasympathetic tend to be closer to the target organs = long pre-ganglionic fibres & short post-ganglionic fibres