lecture 16 - alcohol metabolism

Question 1

Which organs metabolise alcohol?

Answer 1

Stomach (small amount, first pass), liver

Question 2

What enzyme is needed for the first, rate-limiting step in alcohol metabolism?

Answer 2

Alcohol dehydrogenase

Question 3

What are the metabolites in the pathway of alcohol metabolism?

Answer 3

Alcohol, acetaldehyde, acetate, Acetyl-CoA

Question 4

Why is consuming too much alcohol toxic?

Answer 4

The conversion of alcohol to acetaldehyde by alcohol dehydrogenase is rate limiting - excessive alcohol cannot be converted once the enzymes are used up, so alcohol can only be processes at a certain rate per hour

Question 5

What are the long term effects of excessive acetaldehyde?

Answer 5

Liver cirrhosis, cancers

Question 6

What are the consequences of NAD being used up during alcohol metabolism?

Answer 6

High NADH:NAD ratio means NAD is not available for other metabolic pathways, such as gluconeogenesis and TCA