Monogastric pt 5 Flashcards

1
Q

What are the cells in the gastric glands?

A
  • Surface epithelial cells
  • Mucous neck cells
  • Parietal
  • Stem
  • Chief
  • Endocrine cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What do surface epithelial cells do?

A

Secrete mucous and HCO3 protective function

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What do mucous neck cells do?

A

Secrete thin mucous, cell division

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What do parietal cells do?

A

HCl secretion, intrinsic factor secretion for vitamin B12 absorption

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What do chief cells do?

A

Pepsinogen secretion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What do endocrine cells do?

A

Secrete regulatory substances (somatostatin, gastrin, histamine)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the glands in the cardia?

A
  • Secrete only mucous
  • Alkaline
  • Protective function
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are in the glands in the antrum?

A

No parietal

  • D cells (somatostatin)
  • G cells (gastrin)
  • Chief cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What kind of secretion is HCl?

A

Isotonic for protective and protein denaturation and optimization of pH for proteolysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How is H extrused?

A

Through H/K ATPase where K is recycled

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How is HCO3 reabsorbed?

A

Not significant if healthy through and can cause an alkaline tide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What blocks the H/K ATPase blocker?

A

Omeprazole

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What causes gastrin secretion and what is the source?

A

G cells and ACh

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What causes histamine secretion and what is the source?

A

ECL, mast cells; gastrin, ACh

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What causes ACh secreted and what is the source?

A

Vagus, ENS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What do Gastrin, histamine, and Ach stimulate?

A

H/K ATPase on the luminal side

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What inhibits the H2 receptor (histamine receptor)?

A

Ranitidine, cimetidine

Aren’t as effective as omeprazol

18
Q

What does somatostatin do?

A

Inhibit histamine stimulated HCl secretion. Either by blocking the release of histamine from parietal cells or by inhibiting adenylate cyclase.
Inhibit HCl through G cell release

19
Q

What is pepsinogen?

A

Zymogen that is released and cleaved and activated by low pH to make pepsin, positive feedback where pepsin cuts up more pepsinogen

20
Q

What activates pepsinogen release?

A
  • ACh
  • Peptide hormones
  • Beta adrenergic component
21
Q

What happens when luminal pH gets too low?

A

Gastrin secretion ceases so less pepsinogen and HCl

22
Q

What are the phases of gastric acid secretion?

A
  • Basal-no secretion
  • Cephalic-30% acid secretion
  • Gastric-Most acid secretion
  • Intestinal
23
Q

What happens during the cephalic phase?

A

Vagal input causes ACh release which binds to parietal cells and causes gastrin release

24
Q

What happens during the gastric phase?

A

Presence of food in the stomach causes distension sensed by stretch receptors and ACh gets secreted. This stimulates G cells (low pH eventually turns these off) and Parietal cells and you get HCl secretion

25
Q

What buffers the pH of the lumen?

A

Food in the lumen. This relieves inhibition of G cells by low pH and sustains gastrin and HCl secretion

26
Q

What is the effect of NSAIDs on HCl?

A

This blocks COX1 and 2 which lowers PGE secretion. This causes an increase in parietal cell acid secretion

27
Q

What are the exocrine pancreas secretions?

A
  • Digestive enzymes
  • Electrolytes
  • HCO3
28
Q

What are the secretions of the liver?

A
  • Bile

- Electrolytes (HCO3)

29
Q

What type of enzymes are released from acinar cells?

A

Zymogens that get released into duodenal lumen and activated after cleavage

30
Q

What type of enzymes released from pancreatic acinar cells are there?

A
  • Lipid breakdown
  • Nucleic acid breakdown
  • Protein breakdown
31
Q

What is the pH of pancreatic juice and why is it important?

A

High 8.1 due to HCO3 concentration; Neutralizes luminal acidity and is optimal for enzyme function and micellar solubilization

32
Q

What regulates HCO3 secretion?

A

-ACH
-CCK
-Secretin
-VIP
All stimulate the acinus. ACh and secretin stimulate the duct

33
Q

What is the primary hormone for acinar secretion?

A

CCK

34
Q

What is the main hormone for ductal secretion?

A

Secretin

35
Q

What makes up the epithelial cells of the liver?

A

Hepatocytes

36
Q

What is the origin of bile?

A

Cholesterol (nonsoluble) with bile acids (partially soluble)

37
Q

What is the purpose of bile?

A

Emulsification of dietary lipids

38
Q

Where is bile stored?

A

Gallbladder

39
Q

When are bile acids released?

A

When sphincter of Oddi opens when food is in the lumen and CCK regulation. Released into the duodenum and reabsorbed in the ileum where it recirculates to the liver through the portal vein

40
Q

What happens in species that do not have a gallbladder?

A

Bile is continuously released (horse, rat)