Nitrogen Metabolism Flashcards
Hartnup Disease Cause
Defective nonpolar AA transporter
Trp, Tyr, Ala, Val, Leu, Ile, Phe can’t be processed correctly
Hartnup Disease Manifestation
Similar to niacin deficiency:
Pellagra, amino aciduria, photosensitivity, failure to thrive
Malnutrition often precedes flare up
Hartnup Disease Treatment
Niacin supplementation
Phenylketonuria Types and Causes
Primary - Phenylalanine Hydroxylase Deficiency
Secondary - THB Deficiency
Phenylketonuria Effects
Phenylalanine can’t be synthesized into melanin and tyrosine
Built up Phe is neurotoxic and byproduct causes musty urine odor
Phenylketonuria Testing and Treatment
Post-natal Guthrie test given to all babies
Treat with low Phe diet and supplemented Tyr
Tyrosinemia Types and Enzyme Deficiencies
Type I: fumarylacetoacetate hydrolase
Type II: tyrosine aminotransferase
Type III: p-hydroxphenylpyruvate oxidase
Alkaptonuria Cause and Effects
Homogentisate Oxidase deficiency can’t degrade Tyr
Causes black urine, black spots on bones and arthritis
Gout Cause and Treatment
Uric acid crystal buildup caused by overproduction or underexcretion
Treat with low purine diet and allopurinol
Hyperammonemia Cause
Defective transporters in urea cycle
or
Defective urea cycle enzymes
CPSase I or NAGSase especially
Carbamoyl Phosphate Sythetase I
Properties
Used in urea cycle, in mitochondria, NAG-activated
Carbamoyl Phosphate Sythetase II
Properties
Used in pyrimidine synthesis, in cytosol, PRPP-activated
Jaundice Types and Cause
Physiological - Normal in newborns because UGT hasn’t started working fully yet
Pathological - Baby has to replace RBC’s or liver failure blocking conjugation of bilirubin
