Hyperammonemia causes and effects — Flashcards

Flashcard 1: Hyperammonemia results in excess NH3, which depletes _____, leading to inhibition of the TCA cycle

Answer: -ketoglutarate

Flashcard 2: In the liver, _____ may transfer a molecule of NH3 to the urea cycle, reforming -ketoglutarate

Answer: glutamate

Flashcard 3: What is the most common urea cycle disorder? _____

Answer: Ornithine transcarbamylase (OTC) deficiency

Flashcard 4: Where does the urea cycle occur?

Answer: steps in both the cytoplasm and mitochondria

Flashcard 5: urea cycle

Answer: carbomoyl phosphate synthetase I

Flashcard 6: What is the overall purpose of the urea cycle?

Answer: to get NH4+ from amino acid catabolism into an excretable form

Flashcard 7: carbomoyl phosphate synthetase I

Answer: urea cycle

Extra: N-acetylglutamate

Flashcard 8: In which pathway is ornithine transcarbamylase involved?

Answer: urea cycle

Flashcard 9: In which pathways is carbamoyl phosphate involved?

Answer: de novo pyrimidine synthesis; urea cycle

Flashcard 10: ornithine transcarbamylase (OTC) deficiency

Answer:

Extra: inability to eliminate ammoniasomnolence in infantincreased orotic acid in blood and urine, hyperammonemia (and symptoms thereof)same as tx for any hepatic encephalopathy i.e. restrict protein in diet, benzoate or phenylbutyrate, lactulose XR ornithine transcarbamoylase