Liver Physiology Flashcards
The liver has a large reserve capacity. What percentage of functional liver tissue must be removed before regeneration and recovery are no longer possible?
80%.
In what Rappaport zone does the most hepatocellular regeneration occur?
Zone 1 (the portal area).
Name two agents that inhibit normal liver regeneration?
Pyrollizidine alkaloids and antineoplastic drugs; anti-mitotic.
List three factors which may inhibit liver regeneration.
- Fibrosis bridging the liver lobules.
- Loss of a stroma to build on.
- Lack of portal blood supply.
Fasting hyperbilirubinaemia can be seen in horses in the absence of liver disease. What is the highest bilirubin concentration usually correlated with fasting alone and is this unconjugated or conjugated bilirubin?
6mg/dL unconjugated bilirubin.
What is the mechanism by which icterus occurs in liver disease?
Failure of uptake, conjugation or excretion of bilirubin.
What is the mechanism by which weight loss occurs in liver disease?
Energy demand greater than energy absorbed or metabolised.
What is the mechanism by which ascites occurs in liver disease?
Portal hypertension and lymph leakage caused by cirrhosis or veno-occlusion.
What is the mechanism by which change in liver size occurs in liver disease?
Nodular hyperplasia, tumour, cirrhosis, fatty degeneration.
What is the mechanism by which diarrhoea occurs in liver disease?
Bile deficit malabsorption or intestinal oedema secondary to portal hypertension.
What is the mechanism by which pruritus occurs in liver disease?
Retention of bile salts.
What is the mechanism by which dermatitis occurs in liver disease?
Hepatogenic photosensitisation.
What is the mechanism by which CNS signs occur in liver disease?
Heptic encephalopathy.
What is the mechanism by which tenesmus (+/- rectal prolapse) occurs in liver disease?
Hepatic encephalopathy.
What is the mechanism by which change in faecal colour occurs in liver disease?
Bile pigment deficit or undigested fat.
