Alcohol Metabolism

Question 1

How much alcohol is metabolised by the liver and where does the rest go?

Answer 1

90%

Other 10% is passively excreted in urine and breath

Question 2

How is alcohol metabolised?

Answer 2

Oxidised by alcohol dehydrogenase to acetaldehyde and then to acetate by aldehyde dehydrogenase

*smaller amounts of alcohol can be also oxidised by the CYP2E1 enzyme or by catalase in the brain

Question 3

What happens to the acetate at the end of alcohol metabolism?

Answer 3

It is converted to acetyl CoA and used in TCA. Cycle or for fatty acid synthesis

Question 4

What is the recommended limits of alcohol?

Answer 4

14 units/week spread over at least 3 days for both men and women

Question 5

What is the rate of alcohol metabolism?

Answer 5

1 unit=8g

Elimated at rate ~7g an hour, so about 1 unit an hr

Question 6

What compound in the alcohol metabolism causes hangovers?

Answer 6

Acetaldehyde

Question 7

How is acetaldehyde toxicity normally kept to a minimum?

Answer 7

By aldehyde dehydrogenase (low km for acetaldehyde)- converts it to acetate

Question 8

What can excess NADH and acetyl-coa lead to?

Answer 8

Changes in liver metabolism

Question 9

What are some common conditions that can arise from chronic alcohol consumption? Wha

Answer 9

Lactic acidosis

Hypoglycaemia

Gout (urate crystals)

Fatty liver

Chronic pancreatitis

Question 10

What can be used for the treatment of alcohol dependence and how does it work?

Answer 10

Disulfram

Inhibits aldehyde dehydrogenase so stops acetaldehyde being converted to acetate. Meaning if you drink you just get symptoms of a ‘hangover’

Question 11

What effect does alcohol have on the GI tract?

Answer 11

Damages the cells lining it and disturb the general workings