Exam 2 Flashcards
(94 cards)
What does ADH stand for?
MEOS?
Alcohol Dehydrogenase
Microsomal Ethanol Oxidizing System
How many kcal/gram is Alcohol?
What are its other two names?
7 kcal/gram
Ethyl Alcohol or Ethanol
Where is ethanol readily absorbed throughout?
What happens to it in the blood stream?
Where is it primarily oxidatively degraded at?
GI tract
Unaltered in the bloodstream
Liver
What does the liver first convert ethanol into?
Then what?
What does both steps produce?
Acetaldehyde
Acetate
NADH
What are the three enzyme systems of ethanol oxidation?
ADH
MEOS (aka Cyto P-450 system)
Catalase
Where does the Alcohol Dehydrogenase pathway occur?
What does the dehydrogenase require?
What is the Km for ethanol?
When is enzyme saturated and when can ADH not oxidize ethanol?
Cytoplasm of Liver cells
NAD
1mM or 5 mg/dl
3 to 4 times Km
conc. beyond 4 times Km
What is the toxic level for ethanol?
What allows ethanol to enter cells easily?
What happens when ADH is saturated?
50-100 mg/dl
High lipid solubility
Spill over and metabolism by MEOS
Describe what happens to ethanol
Ethanol –> Acetylaldehyde –> Acetate
Does MEOS directly produce NADH?
No but it creates acetaldehyde which when oxidized produces NADH
Which oxidizing system is able to oxidize a variety of compounds such as ethanol, FA, aromatic hydrocarbons, steroids, barbiturate drugs?
It also is associated with Endoplasmic Reticulum
Microsomal Ethanol Oxidizing System
Certain enzymes of MEOS are “inducible” what does this mean and significance?
Ethanol in high conc. can induce synthesis of these enzymes which results in hepatocytes being able to metabolize ethanol much better
What are two problems associated with acetaldehyde toxicity?
Impedes the formation of microtubules in liver cells
Cause the development of perivenular fibrosis
Does Alcohol Dehydrogenase (used to convert Ethanol to acetaldehyde) deplete or create NADH?
CREATES NADH
Depletes NAD+
What does elevated NADH signal?
Metabolic shift toward reduction so…
Inhibits krebs
Decreased fat burning
Increased FA synthesis (fatty liver)
Lactic Acidemia (Increased lactic acid)
What are the four basic steps of Fatty Acid Oxidation? (NADH is a product)
Oxidation
Hydration
Oxidation
Thiolysis
What are the three basic steps to Fatty Acid Synthesis? (NADPH is a reactant)
Reduction
Dehydration
Reduction
Where do lipids tend to accumulate?
In most tissue where ethanol is metabolized
Fatty liver, myocardium, Renal tubules
What is the reactant, enzyme, and product of TAG synthesis?
DHAP, Glycerol 3-phosphate dehydrogenase, and Glycerol 3 Phosphate
What is the Reactant, Enzyme, and Product for Lactate Production?
Pyruvate, Lactate Dehydrogenase, and Lactate
What is an Acyl?
Fatty acid attached to something
What is a fatty acid?
A carboxyl group and a carbon chain
Study the Chart from Biochem one
DAMMIT
Are the fatty acids on a TriAcylGlycerol usually saturated or unsaturated?
First is Saturated
Second is Unsaturated
Third is Either
Are Triglycerides Oxidized or reduced?
Anhydrous or Hydrous?
How many kcal per gram?
Reduced
Anhydrous
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