BL Exocrine Flashcards
Compare and contrast serous vs mucous acini in histology
Serous - darker - due to zymogens
Mucous - lighter/paler - due to mucin
Describe the submandibular gland in histology
Both serous and mucous acini
Serous - darker
Mucous - lighter
Location of a parotid gland
Anterior to the ear
Describe striated ducts
Look like a gland
Lumen in centre
Nuclei are near the lumen or in middle
Function of striated ducts
Prevent water loss
Staining of the parotid gland
Mostly serous
Dark staining
Staining of sublingual gland
Mostly mucous
Light staining
What is the control of salivary secretion?
Neural stimulation only
What is the portal triad?
Hepatic artery - small
Portal vein - biggest
Bile duct - small + purple on H+E
Hepatic blood supply
Hepatic portal vein - from stomach and intestines
Hepatic artery
Describe a liver lobule
Made up of 6 portal triads
Hexagonal shape
What are kupffer cells?
Function
Specialist macrophages in the sinusoidal linin of the liver
Ingests pathogens and recycles old RBCs
What is the bile canaliculi?
Ducts between hepatocytes that collect bile
Describe the sinusoid
Thinner at either end
Wider in the middle
Incomplete basement membrane
Intercellular gap
Are hepatocytes mono, bi or tri nucleated?
Bi or tri
Describe the structure of hepatcytes
No basement membrane
2 apical membranes on opposite sides
Bile canaliculi flows between hepatocytes
Outline the flow of bile in the liver
Canaliculi
Interlobular tributaries
Peripheral bile ductules
Bile duct
Left and right hepatic ducts
What are Ito/Stellate cells?
Store vitamin A
What are pit cells?
Active form of NK cells
Kill tumour cells in the sinusoid
What happens to Ito cells during liver cirrhosis?
Lose their ability to store vitamin A
Differentiate into myofibroblasts
Produce collagen > liver fibrosis
How must of the liver is damaged in low to mild liver damage + how long does it take to regenerate?
Examples of damage
<50%
7-8 days
e.g. viral infection, alcohol
How must of the liver is damaged in mild to medium liver damage + how long does it take to regenerate?
Examples of damage
Up to 70%
30-40 days
e.g liver transplant, heavy alcohol, drug toxicity
How must of the liver is damaged in medium to severe liver damage + how long does it take to regenerate?
Examples of damage
> 70%
Never
e.g. chronic liver failure, chronic alcohol/drug misuse, suicide attempt
What is stored in the liver
Iron
Copper
Lipid soluble vitamins - A,D,E,K
Glycogen
What is the main constitutive secretion of the liver?
Endocrine - Albumin
Exocrine - bile
What is the main regulated secretion of the liver?
IGF-1
Function of bile
Emulsifies fats
Assist in vitamin K absorption into small intestines
How does the liver differ to the pancreas?
In the liver the same cells (hepatocytes) execute both the endocrine and exocrine function
What do the acini of the pancreas secrete?
Lipase
Amylase
Trypsinogen
Ribonuclease
Deoxyribonuclease
What are the epithelial cells in the mammary gland?
Compound alveolar
