L5/6

Question 1

Hypersecretion is usually the cause of gastric or duodenal ulcers?

Answer 1

duodenal ulcers

Question 2

Parietal cell secrete

Answer 2

HCL

Question 3

Intrinsic factor is req for

Answer 3

VitB12 absorption

Question 4

Intrinsic factor (IF) is ONLY secreted where?

Answer 4

Stomach

Question 5

Dominant regulation of stomach function?

Answer 5

Neural

Question 6

Histamine promotes

Answer 6

H+ secretion in stomach

Question 7

What stimulates gastric acid secretion?

Answer 7

Gastrin

Question 8

What is the negative regulator of gastric secretion?

Answer 8

somatostatin

Question 9

What is secreted in all regions of stomach

Answer 9

Mucus and bicarbonate

Question 10

Where are G-cells in stomach?

Answer 10

Antrum of stomach

Question 11

Grinding function of stomach is localized where?

Answer 11

Antrum and pyloric area

Question 12

What cells secrete intrinsic factor?

Answer 12

Parietal cells (also secrete HCL)

Question 13

Chief cells secrete

Answer 13

Pepsinogens

Question 14

Enterochromaffin-like (ECL) cells secrete

Answer 14

Histamine (powerful stimulator of HCL)

Question 15

D-cells secrete

Answer 15

Somatostatin

Question 16

G-cells secrete

Answer 16

gastrin (stimulate HCL secretion)

Question 17

Why do patients with gastric surgery need vitamin B12?

Answer 17

Loss IF

Question 18

Name the 6 types of secretory cells in the fundus and antrum of the stomach

Answer 18

1. G cells - gastrin
2. Chief cells - pepsinogen
3. ECL - histamine
4. D cells - somatostatin
5. Parietal cells - HCL and Intrinsic factor
6. Mucous neck cells - mucus

Question 19

Name the only ESSENTIAL factor of gastric juice

Answer 19

Intrinsic factor!

Question 20

How many states can the parietal cell take on?

Answer 20

Resting and activated states.

Question 21

What transporter is blocked by omeprazole?

Answer 21

The H/K ATPase antiporter on the luminal side of parietal cell. Prevents the secretion of H+ into lumen.

Question 22

What transporter in the parietal cell accounts for the “alkaline tide”?

Answer 22

HCO3-/Cl- antiporter on basolateral membrane. Net secretion of HCL is paired with net absorption of HCO3- into blood.

Question 23

What is the strongest extrinsic stimulator of gastric secretions?

Answer 23

CN X

Question 24

Name 3 stimulators of H+ secretion by parietal cells

Answer 24

1. ACh - neurocrine
2. Gastrin - endocrine
3. Histamine - paracrine

Question 25

What substance competitively inhibits ACh binding to muscarinic (M3) receptors on parietal cells?

Answer 25

Atropine

Question 26

What substance competes with histamine for the parietal H2 receptor?

Answer 26

Cimetidine

Question 27

What substance binds the cholecystokinin B (CCKB) receptor on parietal cells?

Answer 27

gastrin

Question 28

What binds to CCKB receptors on parietal cells?

Answer 28

Gastrin

Question 29

``` Histamine can potentiate the effects of ____ on parietal H+ secretion? A. Gastrin B. ACh C. Somatostatin D. Gastrin and ACh ```

Answer 29

D. Interpathway gossip. Things that stimulate IP3/Ca2+ help each other.

Question 30

Is gastrin paracrine?

Answer 30

Dude, it's endocrine.

Question 31

Vagovagal reflex

Answer 31

Distention of stomach in response to food stimulates CNX to promote gastrin release

Question 32

Somatostatin-mediated negative feedback of H+ secretion. What's the direct and indirect effect of somatostatin?

Answer 32

INDIRECT: parietal cells - decreases cAMP DIRECT: SS acts on G-cells to decrease gastrin secretion

Question 33

Controversy about long-term effect of PPI...

Answer 33

be aware of it

Question 34

NSAIDS inhibit synthesis of...

Answer 34

prostaglandin. Thus, we promote GI bleeding since lose prostaglandin, which negatively regulates H+ secretion by decreasing parietal intra cell cAMP

Question 35

Which is thin walled? Orad or caudad region of the stomach?

Answer 35

Orad is thin walled. Caudad is thick walled.

Question 36

Vagovagal reflex

Answer 36

AFFERENT: Stretch receptors in stomach promote: EFFERENT: Acid secretion, active relaxation of gastric wall muscle, and gastric motility. CN X Excitatory: ACh and substance P mediated contraction of lower stomach (increase motility) CN X inhibitory: VIP mediated relaxation of fundus

Question 37

In which of the following scenarios would you find simple columnar epithelia, with goblet cells? A. intestinal mucosa B. Gastric ulcer (with intestinal metaplasia) C. Barrett's esophagus D. All of the above

Answer 37

D. All of the above

Question 38

Name 3 factors that promote pyloric sphincter constriction, and slow gastric emptying

Answer 38

ACh via CNX excitatory fibers CCK via duodenal I-cells NE via sympathetics

Question 39

Name 2 factors that promote pyloric sphincter relaxation

Answer 39

VIP and NO, via CNX inhibitory fibers

Question 40

Damage to mucosal barrier, is consistent with A. Gastric ulcer B. Duodenal ulcer

Answer 40

A. Gastric ulcer

Question 41

Which of the following could promote duodenal ulcers? A. Insufficient HCO3- secretion by pancreas B. Gastrinoma (Zillinger-Ellison syndrome) C. Insufficient constriction of pyloric sphincter D. All of the above

Answer 41

D. All of the above

Question 42

Patient X has a high parietal cell mass, and high parietal cell H+ secretion, fatty stool (steatorrhea) and duodenal ulcers. Symptoms subside with omeprazole and cimetidine. These signs are consistent with...

Answer 42

Zillinger-Ellison syndrome (gastrinoma)

Question 43

``` Which ulcer type is associated with loss of mucosal barrier? A. Peptic B. Gastric C. Duodenal D. Peptic and Gastric ```

Answer 43

D. Peptic and Gastric

Question 44

Which ulcer type is associated with H. pylori? B. Gastric C. Duodenal D. Peptic and Gastric

Answer 44

B. Gastric ulcer

Question 45

``` Patients with which ulcer type, surprisingly, can exhibit lower than normal H+ secretion? A. Peptic B. Gastric C. Duodenal D. Peptic and Gastric ```

Answer 45

B. Gastric Lacking negative feedback to gastrin release

Question 46

``` Which of the following is a protective mucosal factor? A. NSAID B. H. pylori C. H+ and pepsin D. Prostaglandin ```

Answer 46

D. prostaglandin

Question 47

``` Which of the following is a damaging factor to mucosal barriers? A. Prostaglandin B. HCO3- C. Growth factors D. Alcohol ```

Answer 47

D. Alcohol