Glands of Digestion: Liver Flashcards
What is the largest gland in the body with exocrine AND endocrine functions?
Liver
What are the general functions of the liver?
Metabolism of lipids, carbs, proteins
Production of blood proteins, factors, non-essential vitamins
Detoxifies blood
Produces hepatic (primary) bile
Stores certain vitamins (ie. vitamin A, B12)
What is an exocrine function of the liver?
Produces hepatic (primary) bile
Why are hexagonal shaped lobules difficult to distinguish in humans?
Due to lack of CT between lobules
What cell types are contained in the liver?
Hepatocytes Kupffer cells (stellate macrophages) Ito cells (hepatic stellate cells) Pit cells Hepatic progenitor cells
What is the composition of hepatocytes?
Microvilliated cuboidal cells with lateral bile canaliculi between adjacent hepatocytes
What are the functions of the hepatocytes?
ALL the general functions of the liver
What allows hepatocytes to collect bile?
Their bile canaliculi
Bile moves from the hepatocytes towards ___ in the portal triad?
Bile duct bronchi
How are hepatocytes arranged?
In rows between hepatic sinusoids like spokes of a wheel
What are Kupffer cells/stellate macrophages?
Resident macrophages that develop from monocytes
What is the function of Kupffer cells?
Phagocytosis of debris and aged RBC; they act like an APC
What are the functions of Ito cells/hepatic stellate cells?
Store lipids for immediate use
Store vitamin A
Produce collagen I, III, IV and growth factors
What are pit cells?
NK cells
What cell type is responsible for regenerative capabilities?
Hepatic progenitor cells
What are the branches of the Portal triads?
Hepatic artery
Portal vein
Bile duct
Lymph vessels
What are hepatic sinusoids?
Dilated, fenestrated thin walled vessels found between rows of hepatocytes
What do hepatic sinusoids carry?
A mixture of venous (75%) and arterial blood (25%)
What is the central vein?
Fenestrated thin walled vessel that collects blood from the hepatic sinusoids
Blood flows from the Portal triad towards the___?
Central vein
What other name refers to the space of Disse?
Perisinusoidal space
Where is the space of Disse located?
Between hepatocytes and fenestrated hepatic sinusoids where blood can directly contact microvilliated surfaces of hepatocytes
Why can the liver take over spleen function in about 24-48 hours?
Flow slows enough in the space of Disse so that cells can interact with the blood and its contents
What is Glisson’s capsule made up of?
Dense irregular CT covered with serosa
Is dense irregular CT the primary kind of CT present in the liver?
Yes, other CT is limited in the human liver
