Liver Metabolism and Water Flashcards
(50 cards)
Functions of the Liver include: (4 main things)
Filtering of ingested materials
Synthesis/Catabolism
Storage of Vit/minerals
Excretion (biliary tree)
Heme Catabolism marker of impairment in plasma
increased bilirubin
Carb metabolism marker of impairment in plasma
increased glucose
Protein synthesis marker of impairment in plasma
increased albumin and increased prothrombin time
Protein catabolism marker of impairment in plasma
increased ammonia and increased urea
lipid metabolism marker of impairment in plasma
increased cholesterol and increased triglycerides
drug metabolism marker of impairment in plasma
increase of drug biological half time
bile acid metabolism marker of impairment in plasma
increased bile acids
symptoms of mild liver disease
typically no outward symptoms, only can be seen as mild chemical changes in the blood
symptoms of severe liver disease
jaundice, bruise easily, bleed profusely, distended abdomen, confusion, loss of consciousness
liver disease impacts what body systems
Central Nervous System, Skin, GI Tract, Cardiovascular, and endocrine
Two special features of liver anatomy
- ) Metabolite exchange between hepatocytes and plasma
2. ) Portal Vein draining from intestine and bile duct
What organ plays a central role in glucose metabolism? Why?
Liver bc it maintains the circulating concentration of blood glucose
Permits the release of glucose by hydrolysis of glucose-6-phospate
Glucose-6-phosphatase
Why is gluconeogenesis a process that occurs in the liver and not the muscle or kidneys?
Muscle has store glycogen but no glucose-6-phospatase
Kidneys have the enzyme in lower concentrations, but no stored glycogen
Where are plasma proteins synthesized and what are some examples?
In the Liver
Ex: Albumin (major one in blood), coagulation factors, plasma alpha and beta globulins, and “acute phase proteins”
an increase in this type of acute phase protein indicates inflammation or infection as it is released by damaged tissue
C-Reactive Protein (CRP) - the most quantitatively marked acute phase protein
Why is the urea cycle important?
Break down of amino acids in the liver produces toxic ammonia and ammonium ions, any ammonia that can’t be detoxified by amidating glutamate to glutamine can be used to synthesize nontoxic urea
component of hemoglobin, myoglobin and cytochromes, and synthesized in most cells of the body
heme
What is the Rate limiting step of heme synthesis, what is it catalyzed by?
Glycine and Succinyl-coA condensation to form 5-ALA in the mitochondia, Catalyzed by 5-ALA synthase
How is heme synthesis controlled?
Heme controls its own synthesis because it is and inhibito for 5-ALA synthase
a catabolic product of heme breakdown - 70% of it is formed by the hemoglobin from dead RBCs
Bilirubin
Biliverden vs Bilirubin transport
Biliverdin is soluble and Bilirubin is insoluble so it needs a carrier protein for transport
how is bilirubin broken down?
catabolized by bacteria and released in feces, some reabsorbed and excreted by liver or kidneys
