GI Hormones and Physiology, C34 P199-203 Flashcards Preview

Section II General Surgery P203Surgical Recall Sixth > GI Hormones and Physiology, C34 P199-203 > Flashcards

Flashcards in GI Hormones and Physiology, C34 P199-203 Deck (45):
1

OVERVIEW
Define the products of the following stomach cells:
Gastric parietal cells
P199

HCl
Intrinsic factor

2

OVERVIEW
Define the products of the following stomach cells:
Chief cells
P199

PEPsinogen (Think: “a PEPpy chief”)

3

OVERVIEW
Define the products of the following stomach cells:
G cells
P199

Gastrin, G cells are found in the antrum
(Think: G = Gastrin)

4

OVERVIEW
Define the products of the following stomach cells:
Mucous neck cells
P199

Bicarbonate mucus

5

OVERVIEW
What is pepsin?
P199

Proteolytic enzyme that hydrolyzes
peptide bonds

6

OVERVIEW
What is intrinsic factor?
P199

Protein secreted by the parietal cells that
combines with vitamin B12 and enables
absorption in the terminal ileum

7

OVERVIEW
Name three receptors on the
parietal cell that stimulate
HCl release.
P199

Think: “HAG”:
1. Histamine
2. Acetylcholine
3. Gastrin

8

OVERVIEW
What is the enterohepatic
circulation?
P199

Circulation of bile acids from the liver
to the gut and back to the liver via the
portal vein

9

OVERVIEW
Where are most of the bile
acids absorbed?
P199

Terminal ileum

10

OVERVIEW
How many times is the entire
bile acid pool circulated
during a typical meal?
P200

Twice

11

OVERVIEW
What are the stimulators of
gallbladder emptying?
P200

Cholecystokinin, vagal input

12

OVERVIEW
What are the inhibitors of
gallbladder emptying?
P200

Somatostatin, sympathetics (it is impossible
to flee and digest food at the same time),
vasoactive intestinal polypeptide (VIP)

13

CHOLECYSTOKININ (CCK)
What is its source?
P200

Duodenal mucosal cells

14

CHOLECYSTOKININ (CCK)
What stimulates its release?
P200

Fat, protein, amino acids, HCl

15

CHOLECYSTOKININ (CCK)
What inhibits its release?
P200

Trypsin and chymotrypsin

16

CHOLECYSTOKININ (CCK)
What are its actions?
P200

Empties gallbladder
Opens ampulla of Vater
Slows gastric emptying
Stimulates pancreatic acinar cell growth
and release of exocrine products

17

SECRETIN
What is its source?
P200

Duodenal cells (specifically the
argyrophilic S cells)

18

SECRETIN
What stimulates its release?
P200

pH < 4.5 (acid), fat in the duodenum

19

SECRETIN
What inhibits its release?
P200

High pH in the duodenum

20

SECRETIN
What are its actions?
P200

Releases pancreatic bicarbonate/enzymes/
H(2)O
Releases bile/bicarbonate
Decreases lower esophageal sphincter
(LES) tone
Decreases release of gastric acid

21

GASTRIN
What is its source?
P200

Gastric antrum G cells

22

GASTRIN
What stimulates its release?
P201

Stomach peptides/amino acids
Vagal input
Calcium

23

GASTRIN
What inhibits its release?
P201

pH < 3.0
Somatostatin

24

GASTRIN
What are its actions?
P201

Release of HCl from parietal cells
Trophic effect on mucosa of the stomach
and small intestine

25

SOMATOSTATIN
What is its source?
P201

Pancreatic D cells

26

SOMATOSTATIN
What stimulates its release?
P201

Food

27

SOMATOSTATIN
What are its actions?
P201

Globally inhibits GI function

28

MISCELLANEOUS
What is the purpose of the colon?
P201

Reabsorption of H(2)O and storage of stool

29

MISCELLANEOUS
What is the main small
bowel nutritional source?
P201

Glutamine

30

MISCELLANEOUS
What is the main nutritional
source of the colon?
P201

Butyrate (short-chain fatty acid)

31

MISCELLANEOUS
Where is calcium absorbed?
P201

Duodenum actively, jejunum passively

32

MISCELLANEOUS
Where is iron absorbed?
P201

Duodenum

33

MISCELLANEOUS
Where is vitamin B12
absorbed?
P201

Terminal ileum

34

MISCELLANEOUS
Which hormone primarily
controls gallbladder
contraction?
P201

CCK

35

MISCELLANEOUS
What supplement does a
patient need after removal
of the terminal ileum or
stomach?
P201

Vitamin B12

36

MISCELLANEOUS
Name the main constituents
of bile.
P202

Water, phospholipids (lecithins), bile
acids, cholesterol, and bilirubin

37

MISCELLANEOUS
What are most gallstones made of?
P202

Cholesterol

38

MISCELLANEOUS
How do opiates affect the bowel?
P202

By stimulating sodium absorption and
inhibiting secretion in the ileum as well as
decreasing GI motility by incoordinated
peristalsis (Therefore, place patients on
stool softeners when dispensing pain
medication)

39

MISCELLANEOUS
Which type of muscle fibers,
smooth or striated, does the
esophagus contain?
P202

Both:
Upper third—striated muscle control
of motor nerves
Middle third—mixed
Lower third—smooth muscle, primarily
under control of vagal motor fibers

40

MISCELLANEOUS
Which electrolytes does the
colon actively absorb?
P202

Na+, Cl⁻

41

MISCELLANEOUS
Which electrolyte does the
colon actively secrete?
P202

HCO⁻(3)  (plays a role in diarrhea causing
the patient to have a normal anion gap
acidosis)

42

MISCELLANEOUS
Which electrolyte does the
colon passively secrete?
P202

K⁺

43

MISCELLANEOUS
What is the gastrocolic reflex?
P202

Increased secretory and motor functions
of the stomach result in increased colonic
motility

44

MISCELLANEOUS
What is the blood supply to the liver?
P202

75% from the portal vein, rich in products
of digestion
25% from the hepatic artery, rich in O2
(but each provide for 50% of oxygen)

45

MISCELLANEOUS
What are Peyer patches?
P202

Nodules of lymphoid tissue with B and T
lymphocytes in the small intestine that
selectively sample lumenal antigens
found in the terminal ileum