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Flashcards in Heme Degradation Deck (13):
1

I like to divide lectures into categories. The heme degradation lecture can be divided into three categories

(1) Heme metabolism (Heme --> unconjugated bilirubin)
(2) Conversion of unconjugated bilirubin conversion to conjugated bilirubin
(3) Metabolism of conjugated bilirubin
(two fates - reabsorption or excretion)

2

What is the Van den bergh reaction?

A coupling of bilirubin with a diazonium salt to form a colored complex

3

Direct =

conjugated

4

Indirect =

unconjugated

5

What compound does biliverdin reductase require?

NADPH

6

Describe the conjugationof biliruubin?

Bilirubin is conjugated to glucoronic acid in the liver

7

What is Gilbert?

reduction in transcriptin of HDP-GT due to a mutation in the promoter region

8

What is Criggler-Najjar Syndrome: Type-1?

Complete absence UDP-GT gene

9

What is Criggler-Najjar Syndrome: Type II?

Mutation in UDP-GT

10

What is Dubin-Johnson?

Mutation in MRP2

11

What is Rotor?

Biallelic inactivating in OAT1B1 & OAT1B3

12

Which compound produced by intestinal bacterial degradation of
conjugated bilirubin gives its yellow color?

Urobilinogen (colorless) but is converted to Urobilin (yellow color of urine) in the kidney

13

What type of hyperbilirubinemia results from cholestasis?
Conjugated vs Unconjugated

Cholestasis is defined as a decrease in bile flow due to impaired secretion by hepatocytes or to obstruction of bile flow through intra-or extrahepatic bile ducts. Therefore, the clinical definition of cholestasis is any condition in which substances normally excreted into bile are retained. The serum concentrations of conjugated bilirubin and bile salts are the most commonly measured.