CHAPTER 2 - LIVER Flashcards
What is the functional units of liver
lobules
what do lobules contain
hepatocytes (liver cells)
what other stuff are in the liver?
capillaries ( sinusoids) lined with kupffer
what is kuffer
another type of cells that perform immune function
what are the 2 fuctions of Kuffer cells
1) remove bacteria and toxins from blood
2) Ingest and breakdown old red blood cells
what is hepatic portal vein
Vein that brings blood from the stomach, and pancreas directly to the liver. ]This blood contains products of digestion.
What are the functions of the liver? (8)
1) Destroy - destroy bacteria in portal blood
2) Metabolize - metabolize drugs, hormones, and toxins
3) Produce - Produce fatty acids, triglycerides, cholesterol, and lipoproteins ( ex. HDL and LDL)
4) Maintain - maintain blood glucose
5) Produce - Produce urea
6) Produce - produce clotting proteins, albumin, angiotensinogen, IGF
7) Produce - Produce bile salts
8) Excrete - Excrete bilirubin in the bile
Kupffer cells are made up of
macrophages
Immune function
Blood from gastrointestinal tract ( Containing bacteria, endotoxins, and microbes) flows to the liver where kupffer cells work to clean the blood
In severe liver disease what happens to the blood coming from intestines?
Shunted and not passed through the liver as a result, bacteria and toxins are not cleaned out and left circulating in the blood.
what does liver metabolize?
Metabolizes fat, carbs and proteins.
what emulsifies fat?
Bile
why do we need to emulsify fats?
it allows fat to be transported into the blood stream.
liver turns fatty acids and glycerol into?
trygleceride and cholesterol
the liver repackage tryglecerides and cholesterol by adding what
proteins
repackaged cholesterol and trygleceride with protein is called
lipoprotein
Lipoprotein is stored as
adipose tissue
what is glycogenesis
coverts glucose to glycogen
what is glycogenolysis
breaks down glycogen to glucose
what is gluconeogenesis
formation of glucose from amino acids/ fatty acids
what releases insulin and glucagon?
pancrease
when is glucagon released?
when blood sugar is low
when is insulin released
when blood glucose in high
Prolonged fasting will lead to
liver converting fatty acids and glycerol into ketone bodies and using that as the bodies source (gluconegenesis)
Protein
Synthesis of plasma proteins ( albumin and globulin)
how does liver work with protein
breaks down amino acids (deamination) –> converts ammonia into urea to be excreted by kidneys
what is the break down of amino acid called
deamination
what is albumin?
major plasma protein that circulates in blood stream
what are the 2 things that albumin do
1) maintains oncotic pressure
2) plays a role in transportation
How does liver work as metabolic detoxification?
alters medication, hormones, and other chemicals to make them less toxic
what is first pass effect
liver reduce drug concentration before it reaches circulation
Why is first pass effect good
diminishes reabsorption and facilitates excretion
prevents accumulation of side effects
what are the example of hormones in metabolic detoxification
- aldosterone
- estrogen
- testosterone
what are the example of chemicals in metabolic detoxification
- alcohol
- barbiturates
What is the hematologic function of liver
synthesize most clotting factors
what clotting factors does liver synthesize?
Vitamin K - fat soluble vitamin required to synthesize clotting factors.
what does vitamin K absorption relies on?
Relies on bile production in the liver
Without fat can vitamin K be stored?
NO
What does vitamin K do
Vitamin K helps by converting some coagulation factors into their mature form.
what plasma protein does the liver make? what does this protein do?
The liver makes albumin. It helps keep fluid into the IVF via oncotic pressure in the vascular system.
What is bilirubin
yellowish pigment that comes in the breakdown of old RBC
What breaks down old red blood cells
Macrophages on the spleen and liver break down old RBC
Bilirubin is a key component of what?
Bile
Does bilirubin dissolve well in blood?
No
what does bilirubin need to do to dissolve in blood
Bilirubin does not dissolve well in the blood and must be transported bound to albumin
What do we have to do in order to make bilirubin water-soluble
The liver conjugates bilirubin to glucuronic acid
In order to be excreted in the bile bilirubin has to be
Conjugated bilirubin ( water- soluble)
Conjugated bilirubin is called
Direct
Unconjugated bilirubin is
Indirect or free bilirubin
Once in the large intestine, bacteria converts bilirubin into
- Stercobilinogen and urobilinogen
Stercobilinogen is what
gives feces its brown colour
what is the path way of bilirubin
Unconjugated –> liver –> unconjugated + glucorinic acid –> conjgated –> Bile –> small intestine –> large intestine
urobinilogen ( by bacteria)
excreated or reabsorbed
Compare conjugated bilirubin and unconjugated bilirubin
Unconjugated - not water soluble
conjugated - water soluble
What is bile required for
Required for emulsification and absorption of fat in the intestinal tract
what is bile made up of
Made up of bile salts, cholesterol, bilirubin, electrolytes, and water.
what is bile? where is it stored
Dark green yellowish fluid produces by the liver and stored in the gal bladder.
Jaundice
Not a disorder but can occur with variety of disease
What is jaundice other name
Hyperbilirubinemia
Jaundice results from
elevated bilirubin
What does jaundice cause
- causes yellow discolouration - can be visible on skin, sclera of the eye, and soft palate.
- May also cause pruritis ( itching)
what are the 3 main types of Jaundice
- Prehepatic - hemolitic
- Hepatic - intrahepatic
- Posthepatic - extra hepatic
Prehepatic jaundice
- results from increase in bilirubin before reaching the liver
- Overproduction of unconjugated bilirubin
what is the main cause of prehepatic jaundice
- excessive hemolysis - break down of RBC
- The liver cannot conjugate the bilirubin fast enough because of the increase load
conditions examples that causes prehepatic jaundice
reactions such as
- hemolytic jaundice of newborn and blood transfusion reaction
Prehepatic jaundice is characterized by
- increased unconjugated bilirubin
- decrease hematocrit
- normal liver enzymes
- urine will appear normal (amber)
