L04: Secretions Of The Stomach

Question 1

What are the cells present in the stomach

Answer 1

Mucous neck cell
Parietal cell
EC like cell 
Chief cell
D cell
G cell

Question 2

What part of the stomach is the majority of the cells

Answer 2

Corpus has parietal and chief cells

Question 3

What does mucous neck cell secrete

Answer 3

Mucous and bicarbonate

Question 4

What does parietal cells secrete

Answer 4

Acid and Intrisic factor

Question 5

What does EC like cells secrete

Answer 5

Histamine

Question 6

What does chief cells secrete

Answer 6

Pepsinogen and lipase

Question 7

What does d cells secrete

Answer 7

Stomatostatin

Question 8

What does G cells secrete

Answer 8

Gastrin

Question 9

How does parietal cells make acid

Answer 9

1) H20 and CO2 combine via carbonic a hydrate to from H2C03
2) H2CO3 dissociates to give H+ and HC03-
3) H+ moves into the H-K pump which brings K+ into parietal cell
4) HC03- enters the blood in exchange to Cl- via Cl-HCO3 exchange on the basolateral membrane (alkaline tide)
5) Cl- enters into the stomach lumen to combine with H+ to form HCl

Question 10

How is HCl regulated

Answer 10

Ach
Histamine
Gastrin

Question 11

What does ECL cells secrete

Answer 11

Histamine

Question 12

What is ECL cells mediated by

Answer 12

Ach

Gastrin

Question 13

What does stomatostatin related by D cells do

Answer 13

Inhibit the release of histamine and inhibits acid production

Question 14

When is stomatostatin released

Answer 14

When there is no ach

Question 15

Apart from stomatostatin what other inhibitors are there of acid secretion

Answer 15

Secretin

Cck

Question 16

Which cell produces secretin

Answer 16

S cells

Question 17

Which cell produces cck

Answer 17

I cells

Question 18

Where is s cells and i cells located

Answer 18

Duodenum

Question 19

What are the pharmacological (drug) inhibitors of acid secretion

Answer 19

Proton pump inhibitors e.g omeprazole

H2 receptor antagonist e.g cimetidine and ronitidine

Question 20

What are the 4 phases of gastric acid secretion

Answer 20

Basal
Cephallic
Gastric
Intestinal

Question 21

What enzyme does ach stimulate

Answer 21

Pepsinogen

Question 22

Which cell secretes pepsinogen

Answer 22

Chief cells

Question 23

What happens to pepsinogen when it is secreted

Answer 23

Converted to pepsin

Question 24

What is the role of pepsin

Answer 24

Initiate protein digestion

Question 25

What inactivats pepsinogen

Answer 25

Little acid production

Question 26

What is the protection of gastric mucosal mediated by

Answer 26

Prostaglandins

Question 27

How is prostaglandins made

Answer 27

Precursor of arachnoidic acid
COX-1 gives prostaglandins for protection
COX-2 fives prostaglandins for inflammation

Question 28

What is the role of NSAID

Answer 28

Supress inflammation and mucosal protection by blocking COX-1 and COX-2

Question 29

What does helicobacter pylori do

Answer 29

Express the enzyme urease

Question 30

What does the enzyme urease do

Answer 30

Convert urea to bicarbonate ions which neutralises the stomach acid

Question 31

What can helicobacter pylori cause

Answer 31

Gastritis
Gastric and duodenal ulcers
Gastric cancer

Question 32

What is the treatment for helicobacter pylori

Answer 32

2 antibiotic and proton pump inhibitors

Question 33

Which vitamin absorption is intrinsic factors necessary for

Answer 33

Vitamin B12

Question 34

What is pernicious anaemia

Answer 34

An autoimmune atrophic gastritis directed against parietal cels and stop absorption of B12