The liver is involved in the ___ of carbohydrates, fat and protein.
metabolism
Where do gluconeogenesis, glycogenolysis, glycogenesis and the urea cycle take place?
among a million other processes
Liver
Where are hormones degraded?
Liver
Which hormone is converted from its inactive to active form in the liver?
Thyroxine to Triiodothyronine
(T4 > T3)
Which vitamin is activated in the liver?
Vitamin D
Which three types of molecules does the liver store?
Vitamins
Metal ions (e.g copper and ion)
Glycogen
What is a protein marker of liver function?
Albumin
Which molecules, involved in coagulation of blood, are synthesised in the liver?
Factors
Albumin is a marker for ___ function.
liver
What phagocytic cells are found in the liver and destroy debris and bacteria?
Kupffer cells
The liver detoxifies substances found in the ___.
Give two examples.
blood
Drugs, alcohol
Where is bile produced?
Where is bile stored?
Liver
Gall bladder
Through which sphincter is bile released? Where does this sphincter lead?
Sphincter of Oddi
2nd part of the duodenum
What event prompts the gall bladder’s smooth muscle to contract?
Which signal molecule is involved?
Which parasympathetic nerve is also involved?
Chyme in the duodenum
CCK
Vagus nerve
Which signal molecule is released during a meal and prompts the Sphincter of Oddi to open?
CCK
Bile is involved in the digestion and absorption of ___.
fat
What component of bile can crystalise to form a gall stone?
Cholesterol
Which antibody is found in bile?
IgA
Which breakdown product of red blood cells is found in bile?
Excess amounts of this product in the blood cause ___.
Bilirubin
jaundice
What is cholelithiasis?
Gall stones IN THE GALL BLADDER
Where do gall stones most commonly appear?
Gall bladder
Common bile duct
What is the most common pathology of the biliary tract?
Cholelithiasis
What surgical technique is used to treat symptomatic cholelithiasis?
Laparoscopic cholecystectomy
keyhole surgery to remove the gall bladder.
Why not ERCP? because ERCP can only remove gall stones in the bile duct
If cholelithiasis isn’t producing symptoms, how may it be treated (instead of cholecystectomy)?
Ursodeoxycholic acid (dissolves the stones)
What is biliary colic?
Colicky abdominal pain caused by a gall stone blocking the bile duct
Which drugs can be used to relieve pain caused by biliary colic?
Atropine
GTN
Which process reabsorbs 95% of the bile salts entering the terminal ileum from the duodenum?
Enterohepatic recycling
If bile salts aren’t reabsorbed by the terminal ileum and returned to the liver, how does the body synthesise it?
Using cholesterol
Which drugs can be used to treat hyperlipidaemia and cholestatic jaundice by blocking bile salt reabsorption?
Bile acid sequestrants
Name a bile acid sequestrant used to reduce cholesterol levels.
Cole–
colesevelam, colestipol, colestyramine
Colesevelam binds to ___ ___ in the terminal ileum, preventing their reabsorption and forcing the body to break down ___ to replenish it.
bile salt
cholesterol
What are the side effects of bile acid sequestrants e.g colesevelam?
Vitamin deficiency (bind to fat-soluble vitamins and block absorption)
GI side effects (constipation, diarrhoea, pain, bloating)
Tastes awful
The liver usually converts ___ drugs to ___ metabolites.
(inactive , active)
active drugs to inactive metabolites
Which drug gains activity when it is metabolised by the liver?
Codeine
turns into morphine.
Sometimes, liver metabolism leaves the activity of a drug ___.
unchanged
What tends to happen in Phase I of drug metabolism?
Some reaction to make it more polar (less active)
e.g oxidation, reduction, hydrolysis
What tends to happen in Phase II of drug metabolism?
A functional group is attached to the polar drug to render it even more polar
What happens to a drug once it has been rendered polar by liver metabolism?
Excretion
Which family of enzymes control oxidation reactions in Phase I of drug metabolism?
Cytochrome P540 monooxygenases
(CYP enzymes)
___ is a component of the R groups in many amino acids.
Nitrogen
High levels of nitrogen is ___ to cells.
toxic
____ is detoxified by the liver to form ___, which is secreted in the urine.
Ammonia
urea
What disease occurs when the liver cannot detoxify ammonia to urea?
Hepatic encephalopathy
What is the end stage of hepatic encephalopathy?
Hepatic failure
Coma
Death
In hepatic encephalopathy, blood levels of ___ are high.
ammonia
Ammonia is also produced by ___ in the gut.
bacteria
Which drug is used to convert ammonia produced by bacteria into safe ammonium?
Lactulose
Which drugs can be used to kill off ammonia-producing bacteria in hepatic encephalopathy?
Antibiotics