Pancreas and Liver Flashcards
What is chyme?
Partially digested contents leaving the stomach
Low pH
Hypertonic
What factors are present in the duodenum to protect it from chyme?
Brunners glands = alkaline mucousa
What factors allows for further digestion of chyme in the duodenum?
Hypertonic = water is pulled into the duodenum lumen
Secretions = from pancreas (enzymes, bicarb) and liver (bicarb, bile)
What hormones does the duodenum release in response to the presence of chyme?
Secretin
CCK
What is secretin?
Acts on pancreas to stim release of bicarb
What is CCK?
Acts acini in the pancreas to release of enzymes
Stim the gallbladder to contract
Stim the sphincter of oddi to relax
Outline the structure/function of the pancreas
Acina = exocrine enzymes
Duct cell = connect acina, produce bicarb
Endocrine cells = insulin, glucagon
What enzymes do CCK stim the pancreas to release?
Active = amylase, lipase
Inactive = proteases (stored in zymogen granules)
When activated proteases include?
Trypsin
Chymotrypsin
Elastase
Carboxypeptidase
How does the pancreatic secretions reach the duodenum?
Pancreatic duct joins with common bile duct = ampulla of Vater
What does the liver secrete in response to chyme?
Bile = emulsifies fat in duodenum so they can be digested by lipases secreted by the pancreas
Where is bile stored?
gallbladder
What does bile consist of?
Bile acids = secreted by hepatocytes, conjugated with AA, far better at emulsifying fats = bile salts
Bile pigments
Cholesterol
Alkaline solution
What are the chief functional cells of the liver?
hepatocytes
What vessel drains blood from the gut to the liver?
Portal vein
Outline the micro anatomy of the liver
Lobule = hexagonal arrangement of cells
Portal triad = branch of portal vein, branch of hepatic artery, bile duct
Sinusoid drains to central vein
Canaliculi = drains bile created by hepatocytes to bile duct
What is the function unit of the liver?
Acinus
3 zones corresponding to distance from the blood supply
Cell at the periphery are better oxygenated as they receive the blood first
Cell at the periphery are more vulnerable to toxins
What is a micelle?
Lipid surrounded by bile salts = now water friendly external layer
Lipids diffuse into intestinal ep cell but bile salts recycled
What are chylomicrons?
Lipid delivered to enterocyte by micelle reforms with apoproteins into = chylomicrons
Enter lymphatic capillaries as too big to travel in capillaries
What is steatorrhoea?
Fatty faeces = pale, floating, foul smelling
When bile acids or pancreatic lipases are not secreted in adequate amounts
The falciform ligament is a remnant of what?
ventral mesentary of the foregut
What is the porta hepatis?
where structures enter and exit the liver
portal vein
hepatic artery
bile duct
Where is the IVC in relation to the liver?
posterior
What is the bare area of the liver?
isnt in covered with peritoneum
in contact with diaphragm
