Quan Flashcards
(43 cards)
What is most of the oxygen usage commited to?
oxidative phosphorylation
What is activation of O2 mediated by at body temperature?
metal ions
___ ___ active metal ions are generally sequestered
Free redox
What are reactive oxygen species?
partially reduced, reactive forms of oxygen
What are the 3 ways of ROS formation?
- O2 with reactive metal
- Mitochondrial electron transfer reactions
- enzymatic reaction
What is oxidative stress balanced by?
ROS producing factors and antioxidants
Oxidative stress generated during ischemia/repurfusion results from?
the disruption of electron transfer chain
How does ROS damage cell membranes?
by interacting with polyunsaturated fatty acids to create lipid peroxide
How does ROS damage DNA
by causing DNA break
How does ROS damage protein function
oxidize amino acids
What is ROS important for?
production of bioactive molecules and for the killing of bacteria
What is a critical enzyme in bacterial killing?
myeloperoxidase
What three mechanisms is ROS defended by
prevention
repair
physical barrier
Name 6 antioxidant defenses
SOD catalase Vitamin A Vitamin C Vitamin E glutathione
liver serves as a ___ for all ____ ___
filter
digested materials
What has a broad range of synthetic and catabolic functions?
hepatocytes
Where is metabolic waste secreted into?
biliary tree
Where does the biliary tree drain into ?
Small intestine and excreted in feces
What can hepatic malfunction lead to
Increased: bilirubin glucose albumin prothrombin time urea cholesterol drug half-life bile acids
what does the portal vein drain?
metabolites of the gut to liver
What does glucose-6-phosphatase do
it is a key enzyme in the liver that permits the release of free glucose to the blood
What are 3 liver proteins?
albumin, coagulation factors and acute phase proteins
What does C-reactive protein (CRP) do?
critical phase protein that responds to inflammation or infection
What is the urea cycle essential for?
removal of nitrogen generated by amino acids, thereby preventing ammonia toxicity
