Physiology and Pharmacology of the Liver

Question 1

How is carbohydrate metabolism regulated

Answer 1

Hormonally

Question 2

Glycolysis

Answer 2

Breakdown of Glucose to pyruvate –> lactate (anaerobic) + acetly coA (aerobic)

Question 3

Gluconeogenesis

Answer 3

AA –> Glucose

Question 4

Glycogenesis

Answer 4

Store glucose as glycogen

Question 5

Glycogenolysis

Answer 5

Releasing glucose as required

Question 6

fat Metabolism of the Liver

Answer 6

Ketogenesis
Processing chylomicrons
Synthesis of lipoproteins and cholesterol

Question 7

Horomones deactivated by liver

Answer 7

Insulin
Glucagon
ADH
Steroid hormones

Question 8

Hormones activated by the liver

Answer 8

Thyroid Hormone

Vit D hormone

Question 9

What does the liver store

Answer 9

Fat soluble vitamins - vit A (in cell), D, E, K (hepatocytes)
Water solumble vitamin D
Iron
copper
Glycogen

Question 10

Detoxification

Answer 10

Exogenous
- ethanol and drugs
Endogenous
- bilirubin (haem breakdown)

Question 11

Protection

Answer 11

Kuppfer Cells
Immune Factors (acute phase protein)

Question 12

Synthesis of proteins

Answer 12

Clotting factor 2, 7, 9, 10
Protein S and C
Albumin
Carrier proteins
Apoliproteins
Complement proteins

Question 13

What is the role of bile

Answer 13

Digestion and absorption of fats

Excretion of metabolism product

Question 14

What is bile produced by

Answer 14

Bile duct cells

Hepatocytes

Question 15

Bile action between meals

Answer 15

Stored and concentrated in the gallbladder

Question 16

Bile during a meal

Answer 16

Chyme in duodenum stimulates gallbladder to contract via CCK and vagal impulse
Sphincter of Oddi opens via CCK
Bile spurts into duodenum via cystic and common bile duct

Question 17

How do heapatocytes secrete bile

Answer 17

Secrete primary juice into caniculi which drains into biliary ductules and ducts

Question 18

What are secretions from hepatocytes made up of

Answer 18

Bilirubin
Bile salts
Bile Acids
Lipids and phospholipids
Cholesteral
Na, K, Cl, HCO3, Ca
IgA

Question 19

Excessive cholesterol in comparison to bile may lead to

Answer 19

Acids + Lectin –> Microcystals –> gallstones

Question 20

What is the ost common pathology of the biliary tree

Answer 20

Choleliathiathis

Question 21

What is the gold standard treatment for symptomatic gallstones

Answer 21

Laparascoipc cholecystectomy

Question 22

What is given to patients with unimpaired gallbladder function who have small to medium sized gallstones

Answer 22

Ursodeoxycholic acids

Question 23

What may be given for biliary colic

Answer 23

Strong analgesic

- however morphine can block sphincter of Oddi

Question 24

What can biliary spasm be relieved by

Answer 24

GTN

Atropine

Question 25

Where do bile salts entering the duodenum go

Answer 25

Only a small amount is lost in faeces | Most reabsorbed by active transport in terminal ileum and undergoes enterohepatic recycling

Question 26

A fraction of bile salts are dehydroxylated to what

Answer 26

Secondary bile acids then go to liver then conjugated with glycine or taurine to form bile salts

Question 27

What provides the majority of cholesterol excretion

Answer 27

Bile salts

Question 28

What is the mechanism of colveselam

Answer 28

Binds to bile acids preventing cholesterol from binding and causes its excretion out the body Cholesterol must form more bile acid and will therefore not gather in plaques causes blockages

Question 29

What is colveselam used for

Answer 29

Lipid lowering Cholestatic jaundice Bile acid diarrhoea

Question 30

Drugs are described as xenobiotic what does this mean

Answer 30

Not produced normally by the body

Question 31

What do drug metabolism facilitate

Answer 31

Converts parent drugs to more polar metabolites that are not readily excreted by the kidney and therefore allows excretion

Question 32

Phase 1 involves

Answer 32

Oxidation Reduction Hydrolysis Makes the drug more polar

Question 33

CYP450

Answer 33

Group of haem proteins located in the endoplasmic reticulum mediating oxidation reactions

Question 34

Phase 2 involves

Answer 34

Conjugation of a chemically reactive group resulting in inactive proteins

Question 35

What is a common phase 2 reaction

Answer 35

Glucocordination

Question 36

Hepatic Enchepalopathy caused by

Answer 36

Hepatic Failure prevents urea cycle converting NH3 to urea Blood levels of NH3 increase exerting a toxic effect on the CNS Incoordination, coma, drowsiness due to cerebral oedema