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Flashcards in Gastric Secretion Deck (21):
1

Name the 6 cell types involved in gastric secretion

parietal (oxyntic) cells
chief cells
mucous cells
endocrine cells
mast cells
epithelial cells

2

What do parietal cells secrete?

H+
intrinsic factor

3

What do chief cells secrete?

pepsinogen

4

What do mucous cells secrete?

sulfated glycoproteins

5

What do endocrine cells secrete?

gastrin

6

What do mast cells secrete?

histamine

7

What do epithelial cells secrete?

HCO3-
prostanoids

8

Name the 5 functions of gastric secretion

protein digestion - acid and pepsin
inactivation of bacteria, viruses, and parasites
iron absorption - Fe2+ + H+ = Fe3+
intrinsic factor - vitamin B12 absorption
prostanoids - mucosal barrier cyto-protection

9

Name the 4 phases of gastric secretion

basal phase
cephalic phase
gastric phase
intestinal phase

10

Basal phase

that which occurs in the absence of all cephalic, gastric, and intestinal stimulation

11

Cephalic phase

that mediated by sight, smell, taste, swallowing

12

Gastric phase

that mediated by gastric distension and protein concentration

13

Intestinal phase

that mediated by duodenal amino acid concentration

14

Explain the cephalic phase of gastric secretion

vagal nerve stimulates parietal cells via Ach to secrete H+
vagal nerve stimulates G cells via Ach to release gastrin, which stimulates parietal cells to release H+

15

Explain the gastric phase of gastric secretion

distension stimulates G cells to produce gastrin, which stimulates parietal cells to release H+
amino acids and peptides from the food stimulates parietal cells to produce H+
distension also stimulates parietal cells to produce H+

16

Name the 3 receptors in a parietal cell

histamine
acetylcholine
gastrin

17

Where does feline intrinsic factor originate?

pancreas
(mediates ileal cobalamin absorption - vitamin B12)

18

Name the 7 different mechanisms for inhibiting gastric acid secretion

dietary management (decrease gastric distention and protein content)
oral antacids
chemical diffusion barriers (sucralfate)
acetylcholine receptor antagonists (pirenzepine)
histamine receptor antagonists (ranitidine)
gastrin receptor antagonists (proglumide)
H+, K+, ATPase inhibitors (omeprazole)

19

Name the 5 parts of the gastric mucosal barrier

mucosal cell renewal
HCO3- secretion
mucus secretion
mucosal blood flow
prostaglandins

20

5 things that can cause damage to the mucosal barrier

H+ secretion
increased permeability
mucosal disruption
decreased hydrophobicity
apoptosis/necrosis

21

7 causes of gastric ulcers

NSAIDs
glucocorticoids
stress/shock
mast cell disease
lymphoma
gastrinoma
systemic disease