Stomach Secretions

Question 1

What are the digestive functions of saliva?

Answer 1

moisten and lubricate diet, buffering activity, add water to diet to make fluid more isotonic, being starch and fat digestion

Question 2

How does secretin effect saliva?

Answer 2

it stimulates the addition of Na, K, and removal of Cl from saliva

Question 3

What is the esophageal part of the stomach considered?

Answer 3

non-glandular

Question 4

What type of epithelium is in the esophageal part of the stomach?

Answer 4

stratified squamous epithelium

Question 5

What does the esophageal part of the stomach extend to in the horse?

Answer 5

the margo plicatus

Question 6

What are the glandular, non-acid secreting parts of the stomach?

Answer 6

the cardia and pyloric regions

Question 7

What do the cells of the cardia make?

Answer 7

mucous

Question 8

What do the glands of the pyloric region make?

Answer 8

mucous

Question 9

What do the enteroendcrine cells of the pyloric region secrete?

Answer 9

gastrin

Question 10

What is the glandular, acid secreting part of the stomach?

Answer 10

the fundic portion

Question 11

What types of cells are located in the fundic portion of the stomach?

Answer 11

mucous secreting cells, parietal cells, chief cells, enteroendocrine cells

Question 12

What do parietal cells make?

Answer 12

HCl and intrinsic factor

Question 13

What do chief cells make?

Answer 13

pesinogen, rennin, and other enzymes

Question 14

What do enteroendocrine cells release?

Answer 14

various endocrine and paracrine hormones

Question 15

Where are mucous cells found?

Answer 15

in gastric puts interspersed throughout columnar epithelium of gastric glands

Question 16

What is the function of mucous in the stomach?

Answer 16

protect the stomach from acids and enzymes

Question 17

What is intrinsic factor vital for?

Answer 17

the absorption of vitamin B12

Question 18

What is pepsinogen?

Answer 18

a proteolytic enzyme pre-cursor

Question 19

What happens when pepsinogen comes in contact with acid made by parietal cells?

Answer 19

it is cleaved to form pepsin

Question 20

What does peptin do?

Answer 20

cleaves proteins at aromatic amino acids

Question 21

What is the secretion of pepsinogen stimulated by?

Answer 21

gastrin

Question 22

Where are entero-endocrine cells found?

Answer 22

at the base of gastric glands in mostly fundus an pyloric regions

Question 23

What can entero-endocrine cells make?

Answer 23

glucagon, somatostatin, histamine

Question 24

What are G-cells?

Answer 24

specialized enteroendocrine cells found in the pyloric stomach area that release gastrin

Question 25

What are G-cells stimulated by?

Answer 25

rising pH of chyme, stretch of stomach, vagal stimulation, and peptides/amino acids stimulate chemoreceptors within the mucosa

Question 26

What is the function of parietal cells aside from making HCl and intrinsic factor?

Answer 26

transfer Cl into the lumen of the gastric glands and remove Na and K from the gastric gland lumen fluid making the SID more negative and lowering the pH

Question 27

During active acid secretion from the stomach, what is the pH of the blood?

Answer 27

alkaline

Question 28

What stimulates acid secretion?

Answer 28

vagus nerves, gastrin, and histamine

Question 29

What causes the corteex to activate vagal efferent pathways to stimulate acid secretion?

Answer 29

thought, smell, or taste of food

Question 30

What turns on histamine release?

Answer 30

gastrin

Question 31

How does histamine stimulate acid secretion?

Answer 31

it acts on H2 receptors on parietal cells to simulate acid secretion

Question 32

What do gastrin and histamine raise the level of before acid production?

Answer 32

intracellylar cyclic AMP levels

Question 33

What suppresses gastrin production?

Answer 33

acid

Question 34

What hormones have a minor role in inhibiting acid production?

Answer 34

VIP, GIP, Eteroglucagon, CCK-PKZ

Question 35

Since secretin does not inhibit acid production, what does it do?

Answer 35

it works on the pancreas, Brunner's glands, and salivary glands to enhance alkaline secretions production

Question 36

Where is prostaglandin E1 and 2 and PGI2 produced by?

Answer 36

mucosal cells of the stomach and intestine

Question 37

What is prostaglandin E1 and 2 and PGI2 produced in response to?

Answer 37

excessively low pH and damage to mucosa

Question 38

What do prostaglandin E1 and 2 and PGI2 do?

Answer 38

increases mucus production, decrease H2 mediated acid secretion, inhibits gastrin secretion, increases blood flow to help renew and repair cells

Question 39

How do NSAIDs cause ulcers?

Answer 39

they block PGE1 and PGI2 to decrease mucus production, increase acid production, and decrease blood flow to damaged mucosa

Question 40

What are the type of cells that line the horses stomach?

Answer 40

non-glandular stratified squamous epithelium and glandular epithelium

Question 41

What does the non-glandular epithelium of the horse's stomach get protection from?

Answer 41

prostaglandin E and I2

Question 42

What does the glandular eptihelium of the horse's stomach get protection from?

Answer 42

it secretes a mucus-Na bicarbonate layer that serves to protect the stomach lining by preventing acid from getting direct contact with it

Question 43

What is special about acid production in horses?

Answer 43

it happens continuosly

Question 44

If you were to find horse bots, where in the stomach would you find them?

Answer 44

in the non glandular part

Question 45

Where are stomach ulcers usually found in swine?

Answer 45

in the cardia of the stomach

Question 46

What are common symptoms associated with stomach ulcers in swine?

Answer 46

anemia and melena (dark stool)

Question 47

What nutritional factors can lead to stomach ulcers in swine?

Answer 47

finely ground feed (particularily corn), restricted availability of water or feedm low vitamin E and selenium

Question 48

What bacteria is associated with ulcers across species?

Answer 48

helicobacter