GI Glands Histo

Question 1

Main Digestive Glands

Answer 1

1. Major salivary glands
2. Exocrine pancreas
3. Liver

Question 2

Divisions of salivary glands

Answer 2

CT capsule with septa – lobes – lobules

Question 3

Functions of saliva

Answer 3

• Lubricates/cleanses oral mucosa
• Contains Igs, minerals, electrolytes, buffers, enzymes, metabolic wastes
• Aids in digestion w/ enzymes

Question 4

Path of saliva flow

Answer 4

Acinus – Intercalated duct – striated duct – excretory duct

Question 5

Intercalated duct epithelium

Answer 5

Low cuboidal epithelium

Question 6

Striated duct

Answer 6

Simple cuboidal to columnar epithelium

Question 7

Excretory duct

Answer 7

Simple cuboidal to pseudostratified columnar or stratified cuboidal

Question 8

Parotid gland

Answer 8

• largest salivary gland
• mostly serous secretory cells
• large amounts of adipose tissue
• CN VII passes through

Question 9

Sublingual gland

Answer 9

• Mixed gland (mostly mucus though)
• Lacks defined capsule
• Poorly developed ducts

Question 10

Submandibular gland

Answer 10

• Serous cells predominant
• Mucous cells capped by serous demilunes (bonnet)
• Myoepithelial cells control secretions
• Shorter intercalated ducts vs. parotid
• Longer striated ducts vs. parotid

Question 11

Functional unit of exocrine pancreas

Answer 11

Serous acinus

Question 12

Cells in acinus

Answer 12

Centroacinar cells

Question 13

Centroacinar cells

Answer 13

• Low cuboidal epithelium of intercalated duct

- Secrete HCO3-, Na+, H2O

Question 14

Hallmark for acinar cells

Answer 14

Stain intensely

Question 15

Hallmark for centroacinar cells

Answer 15

Stain lightly

Question 16

Where do zymogen granules originate?

Answer 16

Pancreatic acinar cells

Question 17

Pancreatitis

Answer 17

Zymogens prematurely activated – autodigestion of pancreas – acute pancreatitis or eventual chronic pancreatitis

Question 18

Where does blood mix in liver?

Answer 18

Sinusoids of the lobules

Converges @ central venule – sublobular veins

Question 19

Flow of bile

Answer 19

Right/left hepatic bile ducts – hepatic duct – common bile duct – gallbladder

Question 20

Terminal hepatic venule

Answer 20

• AKA central vein

- Collects blood from sinusoids

Question 21

Portal areas/canals

Answer 21

@ angles of hexagon

loose CT house portal triads

Question 22

Perisinusoidal space of Disse

Answer 22

• Separates hepatocyte plates from blood sinusoidal space
• Site of material exchange b/w blood and liver cells
• No significant barrier b/w blood plasma and hepatocyte plasma membrane

Question 23

Periportal space (space of Mall)

Answer 23

• Located at edges of canals between stromal CT and hepatocytes

Question 24

Kupffer cells

Answer 24

• Specialized macrophages found along endothelial lining of hepatic sinusoids
• Detect/phagocytose erythrocytes

Question 25

Central axis of portal lobule?

Answer 25

Bile duct (middle of 3 central vv.)

Question 26

Area of liver acinus most sensitive to toxins?

Answer 26

"Zone 1" - medial most (farthest from central v.)

Question 27

Area of liver acinus most sensitive to ischemia?

Answer 27

"Zone 3" - lateral most (closest to central v.)

Question 28

CHF and hepatocytes

Answer 28

Most severe effects of ischemia seen in "Zone 3" | "Ischemic necrosis"

Question 29

Classic lobule (of liver)

Answer 29

Emphasizes endocrine function of hepatocytes as blood flows toward central v.

Question 30

Portal lobule (of liver)

Answer 30

Emphasizes hepatocytes' exocrine function and flow of bile from classic lobules toward bile duct in portal triad

Question 31

Hepatic acinus

Answer 31

Emphasizes different oxygen and nutrient contents of blood @ different distances along sinusoids * Location determines function

Question 32

Hereditary hemochromatosis

Answer 32

Increased iron absorption and accumulation in lysosomal hepatocytes

Question 33

Wilson's disease

Answer 33

Hereditary disorder of copper metabolism w/ excessive deposits of copper in liver and brain

Question 34

Chronic liver disease

Answer 34

Perisinusoidal cells remain in quiescent, nonpoliferative state, but proliferate when activated by Kupffer cells and hepatocytes

Question 35

Long-term effects of EtOH

Answer 35

- Fatty liver - Steatohepatitis - Hepatitis

Question 36

Acute Hepatitis

Answer 36

Loss of appetite, nausea, vomiting, jaundice

Question 37

Chronic Hepatitis

Answer 37

Defined by presence of fibrosis, hepatocyte necrosis and inflammatory lymphocytic activity

Question 38

Gallbladder

Answer 38

- Highly folded mucosa w/ simple columnar epithelium (microvilli present) over a lamina propria - Muscularis w/ bundles of muscle fibers to facilitate GB emptying - External adventitia against liver - Serosa when exposed to peritoneal cavity

Question 39

Rokitansky-Aschoff sinuses

Answer 39

- Deep diverticula of mucosa extending through muscularis externa - D/t hyperplasia and herniation of epithelial cells through ME - Bacteria accumulates -- inflammation -- potential gallstones