Chapter 23 - Functions of the Liver
Due to exposure to drugs (especially alcohol), viral infection, ischemia
Cirrhosis is due to the exposure of what?
No chronic infection
Hepatitis A is transient, what does that mean?
Treatment can reduce viral load and slow disease progression (difficult and expensive, but high success rate)
How can treatment help Hep C?
Stores, synthesizes, and release glucose from glycogen
How does the liver impact carbohydrate metabolism?
Changes the structure of drugs and hormones; will metabolize different drugs at different rates
How does the liver inactivate drugs?
Converts excess AA's to glucose and lipids
How does the liver influence amino acid metabolism?
Neutralizes toxic breakdown products of amino acids
How does the liver influence waste product removal?
Regulates circulating triglyceride, fatty acids, and cholesterol
How does the liver regulate the lipid metabolism?
Transmitted contaminate blood transfusions, shared needles an RARELY by sexual contact
How is Hepatitis C transmitted?
Largest blood reservoir in the body
How much blood does the liver hold?
Results in bile backing up into the liver
What is the result of cholestasis in the liver?
Synthesis of plasma proteins
What is the second hematological regulation function?
Synthesis and secretion of bile
What is the sixth hematological function?
Removal of circulating hormones
What is the third hematological regulation function?
Makes lipoproteins, cholesterol, bile salts
What lipid substances does the liver make?
Composition of circulating blood, nutrient metabolism, waste product removal, nutrient storage, drug inactivation
What metabolic activities does the liver regulate?
Iron
What minerals does the liver store?
Fat solubles vitamins (A,D,E, and K) and B12
What vitamins does the liver store?
Receives 25% of cardiac output
How much blood does the liver receive from the heart?
85%
How much cholesterol is produced by the liver?
Infected become chronic carriers
Once a person is infected with Hep B, what are they?
Replaced with connective tissue
What are hepatocytes replaced with?
Corrects nutrient deficiencies by mobilizing stored reserves or performing synthetic activities
What can the liver do with the stored nutrients?
bilirubin builds up in blood
What builds up in the blood as a result of cholestasis?
Caused by cancer, gallstones, scaring
What causes Cholestasis?
Extract nutrients or toxins from the blood
What do liver cells extract from blood?
Liver removes and stores excess nutrients
What does the liver do with nutrients from the blood?
Synthesizes glucose from some amino acids, other sugars
What does the liver synthesize glucose from?
Liver structure and function are compromoised
What happens to the liver structure and function?
Blockage of hepatic ducts
What is Cholestasis?
Widespread destruction of hepatocytes
What is Cirrhosis?
A yellowing of skin and sclera (white of eye) with intense itching (pruritus)
What is Jaundice?
Transmitted by change of bodily fluids
What is Serum Hepatitis caused by?
Jaundice and tissue damage
What is a result of cholestasis?
Jaundice
What is a sign and symptom of liver disease?
Hepatitis B
What is another name for Serum Hepatits?
Hepatitis A
What is another name for infectious hepatitis?
Inflammation of the liver that is most often caused by a virus
What is hepatitis?
Results from ingestion of food (often water, milk , or shellfish) contaminate with virally infected fecal waste
What is infectious hepatitis caused by?
Removal or storage of toxins (DDT and some drugs)
What is the fifth hematological function?
Removal of antibodies
What is the fourth hematological regulation function?
Infected become chronic carriers
Once a person is infected with Hep C, what are they?
Phagocytosis of old or damaged blood cells and antigen presentation to stimulate immune system
The liver performs 6 hematological regulation functions, what is the first one?
Cumulative liver damage, increased risk of liver cancer
What are long term effects of Hep B?
Significant liver damage in 1/2 of infected individuals
What are long term effects of Hep C?
Carbohydrate metabolism, lipid metablism, amino acid metabolism, waste product removal, vitamin storage, mineral storage, drug inactivation
What are the metabolic activities of the liver?
Metabolic regulation, hematological regulation, bile production
What are the three functions of the liver?
Before it reaches systemic circulation through hepatic veins
When do liver cells extract nutrients and toxins from the blood?
Enters hepatic portal system and flows into liver
Where does all blood leaving absorptive surfaces of the digestive tract enter?
Inability to metabolize bilirunin causes yellow color
Why do the skin and the eyes get yellow?