GI Overview/Motility

Question 1

Where’s Meissner’s Plexus located at?

Answer 1

Submucosal Plexus of Meissner

Question 2

Eponym for the Myenteric Plexus?

Answer 2

Auerbach

Question 3

Where is Auerbach’s Myenteric Plexus located at?

Answer 3

Between the outer longitudinal and inner circular layer

Question 4

Components of Enteric Nervous System?

Answer 4

1. Myenteric Plexus of Auerbach
2. Submucosal Plexus of Meissner

PARASYMPATHETIC

Question 5

What does an activation of the SYMPATHETIC nervous system induce?

Answer 5

1. ⬇️Motility
2. ⬇️Secretion
3. ⬆️Sphincter constriction

Question 6

Neurotransmitters of the Enteric Nervous System (Parasympathetic) ?

Answer 6

1. AcH—> ⬆️Motility and Secretions
2. VIP—> ⬇️Sphincter tone (relaxation)
3. GRP (Gastrin Releasing Peptide): Well, you know

Question 7

Hormones that inhibit gastric motility and secretion?

Answer 7

1. Secretine
2. CCK
3. GLP (glucagon-like peptide)
4. GIP (gastric inhibitory peptide)

Question 8

Where is Gastrin secreted?

Answer 8

1. G Cells (Gastric Antrum and Duodenum )

Question 9

Gastrin action?

Answer 9

1. ⬆️H+ secretion

2. ⬆️Gastric Mucosa and Motility

Question 10

Where is Secretin secreted?

Answer 10

1. S cells of Duodenum

Question 11

Secretin function?

Answer 11

1. ⬆️HCO-3 secretion (Pancreas)

2. ⬇️Motility and acid secretion

Question 12

CCK action in gallbladder and pancreas?

Answer 12

1. ⬆️Gallbladder contraction
2. ⬆️ Oddi’s sphincter relaxation
3. ⬆️Pancreas enzyme secretion

Question 13

What do GIP and GLP have in common in terms of action in the Pancreas ?

Answer 13

1. ⬆️Insulin release

2. ⬇️Glucagon release

Question 14

Pacemaker of the intestines?

Answer 14

Interstitial Cells of Cajal

Question 15

Mechanism by which VIP relaxes sphincters?

Answer 15

1. ⬆️NO—> relaxation