Physiology of Liver and Pancreas (Lec 14) Flashcards
What are the two pathways of blood flow through the liver lobule?
portal vein -> sinusoids -> central vein -> hepatic veins
hepatic artery -> sinusoids ->central vein -> hepatic veins
Liver cell plates are composed of two layers of what?
hepatocytes
___ ___ lie between two layers of hepatocytes in each cell plate
bile canaliculi
Sinusoids are lined with what two types of cells?
endothelial cells and Kupffer cells
Where is space of Disse found?
between endothelial cells and hepatocytes
True or false?
Liver has low blood flow and high vascular resistance
false; high blood flow and low vascular resistance
In regards to liver vascular supply, 1050ml from portal vein + 300 ml from hepatic artery flows into ___ every minute
sinusoids
In regards to liver vascular supply, __% is resting cardiac output
27
Portal pressure into the liver = ___ mm Hg
9
Pressure form liver to vena cava = ___ mm Hg
0
What is the effect of cirrhosis on blood flow?
increases blood resistance to blood flow
What is the effect of clot blocking portal vein or a major branch of the liver?
blockage of return blood from spleen and intestines; increase in capillary pressure in intestinal wall -> loss of fluid -> death
In regards to liver vascular supply, what is the normal volume of the liver?
450 ml (10% of body’s blood volume)
High pressure in right atrium -> back pressure on liver -> increased blood volume in liver up to ___ liters
- 5
note: may occur during cardiac failure with peripheral congestion
True or false?
Liver can store blood in times of excess and supply blood in times of diminished volume
true
Hepatic sinusoids are highly permeable to what?
proteins
Efferent lymph has a protein concentration of __ g/dl
6 (almost equivalent to plasma concentration)
True or false?
There is a lower than normal pressure in hepatic veins
false; higher
Back pressure in the hepatic veins causes fluid to transude into ___
lymph
Fluid from the hepatic veins leaks through ___ __ into abdominal cavity
liver capsule
In regards to higher than normal pressure in hepatic veins, fluid is almost pure __
plasma
Large amount of fluid in abdominal cavity = ?
ascites
Carbohydrate metabolism is a function of the liver. Describe what carbohydrate metabolism does
stores glycogen; converts galactose and fructose to glucose; gluconeogenesis; forms many intermediate products
Oxidation of FAs for energy; synthesis of cholesterol, phospholipids, and lipoproteins; synthesis of fats from proteins and carbs are all aspects of what function of the liver?
fat metabolism
Protein metabolism is a function of the liver. Describe what occurs in protein metabolism
deamination of AAs; formation of urea; formation of plasma proteins; interconversion of various AAs and synthesis of other compounds from AAs
Vitamin storage is a function of the liver. What vitamins are stored in the liver?
Vitamin A; Vitamin D; Vitamin B12
True or false?
Immune function is a function of the liver
true
Fibrinogen; prothrombin; accelerator globulin; factors VII, IX, X are all aspects of what function of the liver?
formation of coagulation factors
Removal or excretion of drugs, hormones, and other substances is a function of the liver. Describe how the liver does this
detoxifies or excretes into the bile: sulfonamides, penicillin, ampicillin, and erythromycin; excretes calcium into the bile; detoxification and removal of ammonia and ethanol
Hepatic bile is ___ and ___ by the liver
produced; secreted
Bile from the ___ is hepatic bile that has been stored and concentrated
gallbladder
What are the components of bile?
bile acids, water and electrolytes, cholesterol and phospholipids, pigments and organic molecules
Cholic and chenodeoxycholic acids are bile acids. What are they synthesized by?
hepatocytes
Deoxycholic acid and lithocholic acid are bile acids. What are they converted by?
bacteria
What is the major pigment in bile?
bilirubin
In regards to bilirubin formation, first, hemoglobin is released by what?
damaged RBCs