Basic GI hormonal control

linijovo's version from 2017-01-19 18:12

Section 1

Question Answer
Name 4 hormones used for GIT regulationGastrin, Cholecystokinin (CCK), Secretin, Gastric Inhibitory Peptide (GIP)
Which cell secretes gastrin and where is it found?G cells, antrum of stomach
Which cell secretes CCK and where is it found?I cells, duodenum and jejunum
Which cell secretes Secretin and where is it found?S cells, duodenum
Which cell secretes GIP and where is it found?K cells, duodenum and jejunum
Which hormone generally inhibits GI hormones, and which cells produce it?Somatostatin, D cells
Which hormone, other than gastrin, stimulates gastric acid secretion? Which cells produce it?Histamine, ECL (enterochromaffin-like) cells. Acetylcholine also stimulates gastric acid secretion.

Section 2

Question Answer
Stimuli for gastrin secretion (3)Small peptides/AAs from digestion, Distension of stomach, Vagal stimulation (gastrin-releasing peptide)
Stimuli for CCK (2)Small peptides/AAs from digestion, FAs and Monoglycerides. (Not triglycerides, they cannot cross intestinal membrane)
Stimuli for Secretin (2)pH < 4.5, Fatty Acids in duodenum
Stimuli for GIP (3)Fatty acids, amino acids, oral glucose
What inhibits gastrin secretion? (2)Low pH, somatostatin
What inhibits CCK?Somatostatin
What inhibits Secretin?Somatostatin
What inhibits GIP?Somatostatin

Section 3

Question Answer
What does Gastrin do? (4)1. Stimulate gastric H+ secretion, 2. Stimulate growth of gastric mucosa, 3. Increase gastric motility, 4. Increase pancreatic secretions
What does CCK do? (6) 1. Stimulate pancreatic enzyme secretion, 2. Stimulate pancreatic HCO3- secretion, 3. Gallbladder contract, sphincter of oddi relax, 4. Decrease gastric emptying (increase time for lipid digestion), 5. Decrease appetite via vagus nerve, 6. stimulates growth of exocrine pancreas and gallbladder
What does Secretin do? (4)1. Stimulate pancreatic HCO3- secretion, 2. Stimulate billiary HCO3- secretion, 3. Inhibit gastrin, 4. Stimulate pepsin secretion
What does GIP do? (2)1. Stimulate insulin secretion from B cells of pancreas, 2. Decrease gastric motility