Liver and Pancreas Flashcards
What are the main functions of the liver?
Detoxification of metabolic waste and drugs/toxins, destruction of RBCs and sorting out remains, synthesizes and secretes bile, synthesizes plasma proteins and lipoproteins, metabolic functions
What’s the strongest attachment of the liver?
Left and right triangular ligaments to the diaphragm
What tissue covers the liver?
Peritoneum
What tissue enters the liver at the hilus and follows the vessels throughout the liver?
Tunica fibrosa
What supplies the liver with blood?
Hepatic artery and portal vein
What is the name of the functional unit of the liver?
Hepatic lobules
How does blood flow through each hepatic lobule?
Flows up through branches of hepatic artery and portal vein supplied to the corners of each lobule, then flows through lobule to the terminal hepatic venule located in the center of each lobule
Where are hepatic sinusoids located?
Between rows of hepatocytes, a form of capillary
What creates bile in the liver?
Hepatocytes in lobules
How is bile moved throughout the liver?
In lobules it flows opposite blood, produced in hepatocytes and then moved to the lobule periphery to the triad which contains branches of the hepatic artery, portal vein, and bile ductiles
What do hepatocytes do?
Produce bile, store carbohydrates as glycogen, produce proteins, and temporarily store lipid
What causes fatty liver?
The permanent loss of liver tissue which can be accompanied by scar tissue or cirrhosis
What cells line the sinusoids of each lobule?
Discontinuous simple squamous endothelium
What are Kupffer cells?
Phagocytic cells that sit on hepatocytes and protrude into sinusoids and engulf particulate matter, resident cells
How are Kupffer cells spaced away from hepatocytes?
Space of Disse
What do hepatic stellate cells do?
Store vitamin A and produce extracellular matrix/collagen
Where is the gall bladder located in the liver?
Between the quadrate and right medial lobes
What types of cells are found in bile canaliculi?
Walls formed from adjacent hepatocytes
What types of cells are found in bile ductules?
Simple cuboidal
What types of cells are found in small ducts?
Simple cuboidal to simple columnar
What types of cells are found in large ducts?
Simple columnar
What types of cells are found in the terminal bile duct?
Stratified columnar
What is the gallbladder?
A muscular sac that stores bile until it is needed by the small intestines to emulsify fat
Which species don’t have gallbladders?
Horses and rats
What stimulates the gallbladder to contract?
Cholecystokinin (CCK) is released by endothelial cells when they are stimulated by the presence of lipid, CCK then signals the gallbladder to contract
What is seen histologically of the gallbladder?
Mucosal folds without villi, submucosa with vessels, lymphatics, and elastic fibers, fibers of muscle running in all directions
How is the pancreas an exocrine and an endocrine gland?
Exocrine: Secretes alkaline substances and inactive digestive enzymes into duodenum
Endocrine: Islet cells produce hormones such as insulin and glucagon
How is the pancreas oriented in the body?
Left limb stretches from middle of stomach to the right side of the abdomen, right limb descends caudally along with descending duodenum
What is the difference between the pancreatic duct and the accessory pancreatic duct?
Pancreatic duct: Smaller, enters around pylorus along with bile duct at major duodenal papilla, may be absent
Accessory: Larger, enters a little farther along the duodenum at the minor duodenal papilla
What are Islets of Langerhans?
Endocrine tissue (Lighter staining) scattered throughout the pancreas
