Alcohol Metabolism Flashcards
Where is alcohol mostly metabolised
In the liver
Where is the remainder of alcohol excreted from if not from the liver
Passively in the urine and on the breath
Outline alcohol metabolism
- alcohol is oxidised by alcohol dehydrogenase to acetaldehyde
- acetaldehyde is oxidised to acetate by aldehyde dehydrogenase
What is the acetate from alcohol metabolism converted into
Acetyl CoA to be used in the TCA cycle or fatty acid synthesis
What enzyme in the brain can metabolise alcohol
Catalase
True or false: cytochrome P450 enzymes can metabolise alcohol
True - but only smaller amounts
What is the recommended limit for alcohol consumption in a week
14 units a week spread over 3 days
What rate is alcohol eliminated at
7 g per hour
What causes a hangover
Accumulation of the toxic metabolite acetaldehyde
What can prolonged alcohol consumption cause
Accumulation of acetaldehyde causing liver damage, fatty liver, alcoholic hepatitis, alcoholic cirrhosis
How does alcohol consumption lead to fatty liver
The increased acetyl CoA causes an increase in fatty acid and ketone body productions which increases the synthesis of triacylglycerols in the liver
Why is there an increase in NADH in the liver in chronic alcoholism
In order to oxidise the alcohol and acetaldehyde NAD+ must be oxidised
What consequences are there due to an increase in NADH in the liver
Lactic acidosis
Hypoglycaemia
Urate crystals causing gout
How does an increase in NADH cause hypoglycaemia
There is inadequate NAD+ for glycerol metabolism so less gluconeogenesis
How does an increase in NADH cause gout
Lactate accumulates in the blood so the kidney cant excrete uric acid as well so this builds up
