Gi 05: Lab - Liver, Gallbladder, Exocrine Pancreas

Front 1

What is the primary cell type in the liver?

Back 1

Hepatocytes (may be binucleate or mononucleate)

Front 2

What kind of cells comprise the parenchyma of the liver?

Back 2

Hepatocytes

Front 3

How are hepatocytes arranged?

Back 3

Anastomosing cords of cells with intervening sinusoids

Front 4

What are sinusoids?

Back 4

Vascular spaces lined by endothelium of sinusoidal lining cells

Front 5

What lines a sinusoid?

Back 5

Sinusoidal Lining Cells (basophilic nuclei)

Front 6

What should we know about how endothelial cells lining the sinusoids are held together?

Back 6

They are NOT held together by extensive tight junctions

Front 7

What do the nuclei in the lumen of the sinusoids belong to?

Back 7

WBCs and sinusoidal macrophages (Kupffer cells)

Front 8

What do Kupffer cells originate from?

Back 8

Monocytes

Front 9

What is one function of the Kupffer cells?

Back 9

Endocytose particles and cell debris

Front 10

Where is the perisinusoidal space (of Disse)?

Back 10

Between the sinusoidal lining cells and the hepatocytes

Front 11

What is the space between the sinusoidal lining cells?

Back 11

Perisinusoidal Space (of Disse)
- Intermediate compartment facilitating the exchange of materials between hepatocytes and bloodstream

Front 12

What is the function of the Perisinusoidal Space (of Disse)?

Back 12

Serves as an intermediate compartment facilitating the exchange of materials between hepatocytes and the bloodstream

Front 13

What kinds of cells reside in the Perisnusoidal Space of Disse?

Back 13

Ito cells (hepatic stellate cells, retinoid storing cells)

Front 14

What three structures lie within the hepatoduodenal ligament?

Back 14

- Common Bile Duct
- Hepatic Portal Vein
- Proper Hepatic Artery

Front 15

What are the structures in this slide?

Back 15

Branches / tributaries of these structures:
- Common Bile Duct
- Hepatic Portal Vein
- Proper Hepatic Artery

(Lymphatic vessels and nerves are present in the portal area, but are more difficult to identify)

Front 16

What type of epithelium lines the lumen of a bile ductule?

Back 16

Simple Cuboidal

Front 17

In the classic liver lobule concept of liver histology, blood flows from the periphery of a hexagonal area toward what structure?

Back 17

Central vein

Front 18

Central veins join together, ultimately to form what large blood vessel?

Back 18

Hepatic veins which ultimately lead into the IVC

Front 19

What do you notice about the tissue of the liver?

Back 19

The tissue is rather homogenous in appearance

Front 20

What do you notice about the 1 µm tissue section of the liver?

Back 20

- Staining intensity is not uniform
- Demonstrates that hepatocytes in different zones of the liver can differ with respect to metabolic activity, glycogen storage, and organelle composition

Front 21

What does this darker zoomed in area of the 1 µm tissue section of the liver show?

Back 21

Hepatocytes containing black material - these are glycogen granules

Front 22

What does this lighter zoomed in area of the 1 µm tissue section of the liver show?

Back 22

- Fewer granules are present in these cells
- Pink-staining lipid droplets make the hepatocyte cytoplasm appear foamy

Front 23

How can you see the bile canaliculi between adjacent hepatocytes?

Back 23

- Using the light microscope and an oil immersion objective
- It is easier to see them on EM (as pictured)

Front 24

What types of intercellular junctions are found at the margins of the canalicular area of adjacent hepatocytes?

Back 24

- Tight junctions
- Gap junctions

Front 25

What are the exocrine functions of the liver?

Back 25

Bile synthesis and secretion

Front 26

In the portal lobule concept of liver histology, bile flows from the periphery of a triangular area bounded by three central veins toward what structure?

Back 26

Bile ductule

Front 27

What is shown in this slide of the liver stroma?

Back 27

Silver-stained reticular fiber, composed of type III fibrillar collagen

Front 28

What is cirrhosis?

Back 28

- A progressive liver disease characterized by diffuse damage to parenchymal cells and fibrosis
- Alcohol by-products or viral-induced inflammation may damage hepatocytes and activate Kupffer cells and Ito cells

Front 29

What do Ito cells do when activated? Results?

Back 29

- Transform from fat- and retinoid-storing cells to myofibroblasts that secrete ECM components into the peri-sinusoidal space
- Broad fibrous bands form in the tissue, sinusoids narrow, and there is increased resistance to blood flow

Front 30

What physical signs might result if the perisinusoidal space of Disse is blocked by ECM components (cirrhosis)?

Back 30

- Jaundice - yellowing of skin, sclera and other tissues
- Ascites - fluid accumulation in the body cavity
- Liver failure

Front 31

Why does jaundice occur from cirrhosis?

Back 31

Hepatocyte damage results in bilirubin accumulation in the tissues, resulting in yellowing of the skin, sclera, and other tissues

Front 32

Why does Ascites occur from cirrhosis?

Back 32

Blood flow from the gut to the liver is diverted due to increased pressure

Front 33

Why does liver failure occur from cirrhosis?

Back 33

Damage to hepatocytes

Front 34

What is the structure of the gallbladder? Location?

Back 34

Small, blind-ended sac attached to the underside of the liver

Front 35

What is the surface of the gallbladder covered in?

Back 35

- Surface attached to the liver is covered with Adventitia
- The free surface is covered in Serosa

Front 36

What is adventitia? Which part of the gallbladder is covered in it?

Back 36

- Outermost CT that surrounds an organ or vessel which is not covered by serosa
- Covers the surface of the gallbladder attached to the liver

Front 37

What is serosa? Which part of the gallbladder is covered in it?

Back 37

- Outermost covering (visceral peritoneum) of an organ that lies within the body cavity
- Consists of a simple squamous epithelium (mesothelium) that secretes a watery serous fluid
- Covers the free surface of the gallbladder

Front 38

What is the function of a serosa?

Back 38

- Simple squamous epithelium (mesothelium) that secretes a watery serous fluid
- Allows the organs of the body cavity to move past each other with minimal friction

Front 39

What type of epithelium lines the lumen of the gallbladder?

Back 39

Simple columnar epithelium

Front 40

The specimen was obtained from the wall of a gallbladder facing which surface?

Back 40

Attached - gallbladder wall blends with the CT

Front 41

What is the function of the gallbladder?

Back 41

Store and concentrate bile

Front 42

How does the gallbladder store and function bile? What structural features facilitate this function?

Back 42

- Concentrates bile by absorbing water
- Apical microvilli on its epithelial cell increases the surface area for this function
- Water is transferred to capillaries in the lamina propria

Front 43

When lipid enters the small intestine, the enteroendocrine cells of the duodenum secrete what hormone? Function?

Back 43

Cholecystokinin causes contraction of smooth muscle in the gallbladder facilitating release of bile.

Front 44

What does this slide of the gallbladder show?

Back 44

- Olive green: smooth muscle of gallbladder wall
- Bright green: collagen fibers
- Red: nuclei and erythrocytes

Front 45

The specimen was obtained from the wall of a gallbladder facing which surface?

Back 45

Free - adipose tissue is present beyond the serosa

Front 46

How is the pancreas subdivided?

Back 46

Parenchyma is subdivided into lobules by CT trabeculae (septae)

Front 47

What can you see in this slide of the pancreas?

Back 47

Pancreatic acinar cells (grape-like clusters of secretory cells)

Front 48

What are the definitive, secretory cells of the body?

Back 48

Pancreatic acinar cells

Front 49

The basal cytoplasm of acinar cells is basophilic due to the presence of which organelle?

Back 49

RER

Front 50

The apical cytoplasm of acinar cells is eosinophilic due to the presence of which organelle?

Back 50

Zymogen granules

Front 51

What is the principle product of the pancreatic acinar cells?

Back 51

Digestive enzymes

Front 52

What are the diagnostic feature of the pancreas? What are they a component of?

Back 52

Centroacinar cells - component of the intercalated ducts

Front 53

What forms the beginning of the duct system?

Back 53

Centroacinar cells

Front 54

What do cells of the intercalated ducts contribute to the exocrine secretion of the pancreas?

Back 54

Bicarbonate and water

Front 55

Intercalated ducts join to form what? What does that structure combine to form? Which drains into?

Back 55

- Intercalated ducts join to form Intralobular ducts
- Inbralobar ducts join to form Interlobular ducts
- Interlobular ducts drain into the Main Pancreatic Duct

Front 56

What is this a picture of?

Back 56

Interlobular Duct

Front 57

What type of duct is present in the parotid gland but absent from the pancreas?

Back 57

Striated Ducts