Alcohol Metabolism Flashcards Preview

Z OLD ESA 1- Metabolism > Alcohol Metabolism > Flashcards

Flashcards in Alcohol Metabolism Deck (26):
1

How is alcohol removed from the body?

90% metabolised by the liver, Remainder excreted passively in urine and on breath

2

What is the main process of alcohol metabolism?

- Alcohol oxidised by alcohol dehydrogenase to acetaldehyde, converting NAD + to NADH
- Acetaldehyde oxidised to acetate by aldehyde dehydrogenase, converting NAD +  to NADH
- Acetate converted into acetyl~CoA

3

What happens to the acetyl~CoA produced in alcohol metabolism?

Used in TCA cycle or for fatty acid synthesis

4

How can smaller amounts of alcohol be metabolised?

- Oxidised by cytochrome P450 2E1 enzyme (CYP2E1) 
- By catalase in the brain

5

What are the recommended maximum units of alcohol?

- 21 units per week for men
- 14 units per week for women

6

How much is 1 unit of alcohol?

8g

7

At what rate is alcohol metabolised?

Eliminated at a rate of ~7g

8

What relationship does alcohol metabolism show?

0 order kinetics- linear elimination

9

What causes a hangover?

Accumulation of the toxic metabolite acetaldehyde

10

How is acetaldehyde toxicity normally kept to a minimum?

By aldehyde dehydrogenase

11

Does aldehyde dehydrogenase have a high or low Km for acetaldehyde?

Low

12

What does excess acetaldehyde cause?

Liver damage

13

What can cause sufficient acetaldehyde accumulation to cause liver damage?

Prolonged and excessive alcohol consumption

14

What effect can excess NADH and acetyl~CoA have on the liver?

Can lead to changes in liver metabolism

15

What conditions can be caused by liver damage?

- ‘Fatty liver’ 
- Alcoholic hepatitis 
- Alcoholic cirrhosis

16

What is fatty liver caused by?

#NAME?

17

Why does increased synthesis of triacylglycerol occur in due to excessive alcohol consumption?

Because there is increased synthesis of fatty acids and ketone bodies because of increased acetyl~CoA (as is the end product of alcohol metabolism), and inadequate NAD +  for fatty acid oxidation as decrease in NAD + /NADH ratio

18

What has happened in lactic acidosis?

Lactate has accumulated in the blood

19

Why does lactate accumulate in the blood in chronic alcohol consumption?

Because inadequate NAD +  for conversion of lactate to pyruvate

20

What is gout?

When urate crystals accumulate in tissues

21

Why does chronic alcohol consumption cause gout?

Because of the kidneys inability to excrete uric acid is reduced because of inadequate NAD +  conversion of lactate to pyruvate (uric acid and lactate share a common excretion pathway)

22

How does chronic alcohol consumption cause hypoglycaemia?

Gluconeogenesis deficit, because inadequate NAD +  for conversion of lactate to pyruvate and for glycerol metabolism

23

What can be used to treat alcohol dependance?

Disulfiram

24

What does disulfiram do?

Inhibits aldehyde dehydrogenase

25

What happens if a patient on disulfiram drinks alcohol?

Acetaldehyde will accumulate, causing symptoms of hangover

26

How is disulfiram administered?

Implanted into patient