(6) Nitrogen Metabolism (Kinde)

Question 1

When renal biochemistry goes wrong, what is typically produced?

Answer 1

Kidney stones!!!

There are 4 types

Question 2

Who are the “stars” of nitrogen flow

In the liver

Extrahepatic tissue

Answer 2

In the liver = Glutamate

Extrahepatic tissue = Glutamine

Question 3

Answer 3

D. Conversion of ammonia to carbamoyl phosphate via carbamoyl phosphate synthase I and NAG activation

Question 4

What is the major source of nitrogen in your body?

Answer 4

Protein

To produce ammonia

Question 5

What is the first step of nitrogen removal?

Answer 5

Oxidative deamination via glutamate dehydrogenase

Question 6

Amino acid resorption defects

Hartnup is due to?

Answer 6

Inability to resorb

NON POLAR AA

Question 7

Amino acid resorption defects

Cystinuria is due to?

Answer 7

Inability to resorb

DIBASIC AA

Question 8

BLUE BOX: HIGH YIELD

Hartnup disease

Caused by?

Answer 8

Autosomal recessive disorder

Defect in transporter of non polar/neutral amino acids

Question 9

BLUE BOX: HIGH YIELD

Hartnup disease

Clinical manifestations?

Answer 9

Manifests in infancy as failure to thrive

Nystagmus

Intermittent ataxia

Termor

Photosensitivity

Question 10

BLUE BOX: HIGH YIELD

Hartnup disease

AKA?

Answer 10

Pellagra-like dermatosis

Question 11

BLUE BOX: HIGH YIELD

Hartnup disease

Triggered by?

Answer 11

Sunlight

Fever

Drugs

Emotional/physical stress

Period of poor nutrition

Question 12

BLUE BOX: HIGH YIELD

Hartnup disease

Treatment?

Answer 12

Niacin repletion

High protein diet

Daily nicotinamide supplementation

Question 13

BLUE BOX: HIGH YIELD

Hartnup disease

Important aa that is a precursor for a LOT??

Answer 13

Tryptophan

Precursor for serotonin, melatonin, niacin (precursor for NAD)

Question 14

Answer 14

C. Niacin

Question 15

Answer 15

D. Phenylalanine

Question 16

Cystinuria has a defective amino acid transporter for the following amino acids:

Answer 16

Dibasic Amino acids, use COAL mneumonic

C | Cystine

O | Ornithine

A| Arginine

L | Lysine

Question 17

Defective amino acid metabolism

Probably talking about

Answer 17

PKU (Phenylketonuria)

Question 18

Classical PKU is due to

Answer 18

Defective phenylalanine hydroxylase (PAH)

If body does not have enough PAH, phenylalanine is not convered to tyrosine

Question 19

Albinism is due to…

Answer 19

Inability to form melanin pigments

No tyrosinase

Question 20

Defects in the ___________________ can lead to secondary PKU

Answer 20

Biosynthesis or regeneration of THB

Question 21

Where do tyrosinemia type I, II and III show up in the phenylalanine to fumarate pathway?

Answer 21

Question 22

Alkaptonuria is due to defective…

Answer 22

Homogentisate oxidase

Question 23

Clinical manifestation of alkaptonuria?

Answer 23

“Black urine disease”

Causes homogenistic acid to accumulate

Question 24

Answer 24

C. Tyrosine

Question 25

Answer 25

C. Homogentisate oxidase

Question 26

Gout is characterized by...

Answer 26

High levels of **urate** in the blood

Question 27

What can cause a gout flare up?

Answer 27

Diets rich in purines (beans, spinach, lentils) Along with (Alcohol, meat and seafood)

Question 28

What is the major treatment for gout?

Answer 28

Allopurinol

Question 29

Answer 29

Sardines, Liver, Sweetbreads, Beans, Beer

Question 30

Answer 30

B.

Question 31

Hyperammonemia occurs with...

Answer 31

Defects in any of the 6 enzymes associated with the **urea cycle** or with **3 specific transporters**

Question 32

What is **carbamoyl phosphate synthetase II?**

Answer 32

Cystolic enzyme unique from the **mitochondria** isoform that functions in the **urea cycle**

Question 33

What are the differences between CPSase I and II?

Answer 33

Question 34

What enzyme is responsible for congugating uncongugated bilirubin?

Answer 34

UDP glucuronyl transferase (UGT)