GI 4 Flashcards Preview

Cell Bio Test IV > GI 4 > Flashcards

Flashcards in GI 4 Deck (28):
1

What are Glisson's capsule?

Dense outer lining of liver
coated by visceral peritoneum (mesothelium)
Continuous with portal canal

2

Describe the classic hepatic lobule

Central vein (terminal hepatic venule)
Portal canals - at outer angles - artery, vein, duct
Sinusoidal capillaries (cells literally bathed in blood)

3

What's the space of mall

Space between peripeheral plates and triad (artery, vein, duct)

Where lymph originates

4

What's the portal triad?

Portal vein, artery, and bile duct in portal canal

5

Tell me about liver blood supply

Dual blood flow

75% comes from portal vein
25% comes from hepatic artery proper

6

What are Kupffer cells?

In sinusoids
Cleanses blood
"bite" red blood cells

7

Sinusoids of liver

Discontinuous endothelium
Discontinuous basal lamina - for rapid transfer of materials

Kupffer cells reside there

8

Perisinusoidal Space (of disse)

Contains Hepatic stellate cell (perisinusoidal cell)
- lots of lipid droplets, Vitamin A, not much activity usually

Between epithelium and membrane of hepatocyte
Microvilli extend into there to more rapidly exchange material

9

Portal Lobule

Exocrine (bile) territory draining into bile duct

This was the triangle from 3 adjacent central veins; the cells there dump the bile into the one central portal canal

10

Hepatic Acinus (of Rappaport)

Diamond shape between 2 adjacent hepatic lobules, contains zones 1, 2, and 3

11

Primary Lobule, (liver lobule)

Like a slice of pie
Pie-sliced area of hepatic lobule
Extends from central vein to 2 sides, including portal triad

12

Zone 1

Higher O2 concentration
Regenerative capacity

Fatty-acid oxidation, glucose-liberating enzymes

13

Zone 3

Fatty-acid synthesizing enzymes
Detox occurs here
- Acetaminophen toxicity causes necrosis here first
Glycolysis enzymes

First to necrose

14

Functions of liver

Detox (in SR)
Glycogen metabolism
Protein synthesis
Bile acid synthesis
Bilirubin conjugation and secretion

15

Gilbery syndrome

Bilirubin conjugation reduced
causes insanity, mental retardation, and possible death around age 28

16

Crigler-Najjar syndrome

Bilirubin conjugation decreased (type II)
or none (type I - fatal)

17

Dubin-Johnson Syndrome

Decreased secretion of conjugated bilirubin, due to absence of MDR-2 canalicular transport protein

pneumonic - Mr. DJ

18

What happens in fatty liver changes/alcohol cirrhosis?

Perisinusoidal cell (hepatic stellate cell) goes crazy

Gets provoked, becomes synthetic - lays down collagen ("and contractility"?)

19

What is the bile canaliculus?

first collecting structure for bile
No ductal cells - simply lined by plasma membrane of hepatocytes

20

Outline the flow of bile

Secreted into bile canaliculus (apical lumen of hepatocytes)

Flows down to a duct - Canal of Herring
- lined simply by ductalar cells

Goes into bile ducts (in portal triads) - simple cuboidal

Hepatic ducts - simple columnar epithelium

21

Where are hepatic stem cells located?

In the canal of herring

22

Layers of the gallbladder (3)

Mucosa
Muscularis
CT layer of serosa/adventitia
adventitia - between gallbladder and liver
serosa - faces peritoneal cavity
Gallbladder cancer metastasizes where there is no serosa (no epithelial lining)

23

Rokitansky-Aschoff Sinuses

Normal - extend through muscularis in gall bladder
Originate in mucosa

24

Cholesterolosis

Macrophages loaded with cholesterol

25

Which cells of the pancreas are endocrine and which are exocrine?

Endocrine - islets of Langerhans

Exocrine - acinar cells

26

What do pancreatic duct cells secrete?

Water
Ions of which HCO3- are important in neutralizing chyme

27

What are two primary causes of acute pancreatitis?

Alcohol and gallstones

Digestive enzymes stored in inactive form in acinar cells; injuring acinar cells causes premature activation of these enzymes

28

What happens if the bile canaliculus is damaged?

Damage to bile canaliculus can cause increase in alkaline phosphatase