9. Histology of the liver, gallbladder, and pancreas Flashcards
What is the largest glandular tissue in the body?
Liver
1200-1500 g
What are the four lobes of the liver? Which two have the most bulk?
RIght, left, caudate, quadrate
RIght and left
The liver is unique in that it receives mainly venous blood directly from:
Spleen
Pancreas
Intestine
**first organ to encounter any injested toxic substances as well as nutrients
The liver is unique in that CT is sparse, and the bulk of the liver is made up of:
Parenchymal cells/ hepatocytes
6 functions of the liver
- Detox of metabolic waste products
- Synthesis of plasma lipoproteins
- Synthesis of clotting factors
- Synthesis, storage, and secretion of carbs and lipids
- RBC destruction and recovery of contents
- Synthesis and secretion of bile
What are the endocrine secretions of the hepatocytes that enter the hepatic blood?
ALbumin Fibronectin Transferrin Prothrombin Lipoproteins Alpha 1 antitrypsin Glucose Thryoxin
What is the main exocrine function of the liver?
Production of bile
What are the four functional groups of liver components?
Connective tissue
Large vessels
Sinusoidal capillaries (sinusoids)
Hepatocytes
What kind of fibers surround the hepatocytes and sinusoids? Layout?
Reticular fibers–type III collagen
Extend outward from the central vein, only CT in the lobule
Supports the parenchyma and keeps the sinusoids open
What do the reticular fibers originate from? How can their disruption be identified?
Stellate/ito cells in the Space of Disse
Staining for reticulin
What are the five main vessel systems in the liver?
Hepatic artery–oxygenated blood to the liver
Hepatic portal vein–venous blood to the liver
Central veins–blood away from the liver toward the hepatic veins, IVC
Bile ducts–bile from the liver
Lymphatic vessels–lymph away from the liver
Arterial capillaries and inlet venules carry blood from the hepatic artery and portal veins into capillaries called
Sinusoids
Portal triad
Hepatic artery
Portal vein
Bile duct
**lymphatic vessels also associated
Sinusoids are made up of two cell types:
Endothelial cells (sinusoidal cells) Kupffer cells (sinusoidal macrophages)
Role of Kupffer cells?
Derivatives of monocytes, probably involved in the breakdown of senile RBCs
Where does exchange of substances between the blood and hepatocytes take place?
Peri-sinusoidal Space of Disse (between the basal surface of the hepatocyte and the sinusoid
How do hepatocytes increase their SA for absorption?
Extend microvilli from the basal surface
What calls are found in the perisinusoidal space?
Stellate
Stellate cells contain ___ and are the major site of ____ stoarage
Lipid droplet
Vitamin A
What is the functional unit of the liver?
Lobule
What are the three ways that the functional unit of the liver can be described?
Classic lobule (hexagon) Portal lobule (triangle between three central veins) Liver acinus
The classic lobule has __ at the center and __ at each of its 6 corners
Central vein
Portal triad