Liver Function Flashcards Preview

Gastrointestinal > Liver Function > Flashcards

Flashcards in Liver Function Deck (36):
1

What is the name given to macrophages with the the sinusoidal spaces in the liver?

Kuppfer cells

2

Where is bile stored?

Gallbladder inbetween meals

3

How is bile released?

When there is chyme present in the duodenum, cholecystikinin is released which opens the sphincter of oddi releasing bile into the duodenum

4

Is bile acidic or alkali?

Alkali

5

What do hepatocytes secrete?

Hepatic bile
Lipids and phospholipids
Cholestrol
IgA
Bilirubin

6

What is the precursor of bilirubin?

Porphyrin component of haemoglobin

7

What happens to urine and faeces if bilirubin is present?

Urine darkens and stools become pale

8

How can metabolism affect drugs?

Can convert drugs into polar metabolites so they can be exrcreted via the renal system

Convert drugs so that they become active metabolites

Convert drugs to metabolites with a different mechanism of action

9

What are the two main phases of drug metabolism?

Phase 1 - Oxidation, Reduction, Hydrolysis
Phase 2 - Conjugation

10

Give an example of the two phases of drug metabolism?

Drug = Asprin
Phase 1 converts it to...
Derivative = Salicylic acid
Phase 2 converts it to...
Conjugate
Glucoronide

11

Describe the monooxygenase cycle.

Drug enters as drug substrate (RH)
Oxygen provides two atoms of oxygen
One of which is added to the substrate to yield the hydroxyl product (ROH)
The other combines with protons to form H2O

12

Give an example of two substances that are subject to phase 2 reactions in the liver (Glucoronidation)

Bilirubin
Adrenal corticosteroids

13

What are the 4 main plasma proteins produced by the liver?

Albumin
Alpha globulins
Beta globulins
Theta globulins

14

What do plasma proteins do?

Maintain osmotic pressure
Transportic hydrophobic substances
Act as pH buffers
They have enzymatic and immune activity

15

What is the most common plasma protein?

Albumin

16

What promotes the production of albumin?

Insulin

17

How much albumin is produced a day?

14g

18

Give an example of a drug that albumin is good at transportin

Asprin

19

How is iron transported around the body?

Transported as ferric ion Fe3+ bound to transferrin

20

How is copper transported around the body?

Ceruloplasmin

21

What are the 5 types of lipoproteins?

Chylomicrons
VLDL
LDL
IDL
HDL

22

Where do chylomicrons originate?

Intestine

23

Where do VLDLs originate?

Liver

24

Where do IDLs originate?

VLDLs

25

Where do LDLs originate?

VLDLs/IDLs/Liver

26

Where do HDLs originate?

Intestine and liver

27

What do chylomicrons do?

Transport of exogenous fat to liver

28

What do VLDLs do?

Transport of endogenous fat to peripheral cells

29

What do IDLs do?

LDL precursor

30

What do LDLs do?

Transport cholesterol to peripheral tissues

31

What do HDLs do?

Reverse cholesterol transport
Removes excess cholesterol from cells
So that it can be transported back to liver to be synthesised

32

Which vitamins does the liver store?

Vitamin A
Vitamin D
Vitamin B12

33

What are the main sites of cholesterol synthesis?

Liver
Also; intestine, adrenal cortex and gonads

34

What is the rate limiting enzyme in the synthesis of cholesterol?

HMG-CoA reductase

35

What are the products of cholesterol?

Vitamin D
Steroid hormones - Corticosteroids, androgens and estrogens
Bile salts

36

What is the level of cholesterol at which there is a risk of atheroma formation?

4.1mmol/L