Lecture 47 Flashcards
Ammonia is very toxic, especially to the _____. The serum level is regulated around _____microM/L by two key enzymes, _______ and _______ because ______ is a major source of ammonia and ______ is a major sink for ammonia.
Ammonia is very toxic, especially to the CNS. The serum level is regulated around 35microM/L by two key enzymes, GLUTAMINE SYNTHETASE and GLUTAMINASE, because GLUTAMINE is a major source for ammonia and GLUTAMATE is a major sink for ammonia.
The expression of Glutamine synthetase and Glutaminase is tissue specific. The kidneys, intestines, and periportal hepatocytes produce _______ but not ______ ______. The brain, muscles, and perivenous hepatocytes produce ______ ______ but not ______.
The kidneys, intestines, and periportal hepatocytes produce GLUTAMINASE but not GLUTAMINE SYNTHETASE. The brain, muscles, and perivenous hepatocytes produce GLUTAMINE SYNTHETASE but not GLUTAMINASE.
_____ provides a nontoxic storage and transport form of ammonia, and it is generated from the conversion of _____ in a reaction that requires ATP + NH4 and is catalyzed by _____ _____.
GLUTAMINE provides a nontoxic storage and transport form of ammonia, and it is generated from the conversion of GLUTAMATE in a reaction that requires ATP + NH4 and is catalyzed by GLUTAMINE SYNTHETASE.
Formation of Urea takes place in the _____, specifically within ______ hepatocytes, and is the most important disposal route for ammonia.
Formations of Urea takes place in the LIVER, specifically in PERIPORTAL hepatocytes, and is the most important disposal route for ammonia.
The sources of Nitrogen in the Urea cycle are as follows: One molecule of N comes from ____ and the other comes from ______ acid.
One molecule comes from NH3 (ammonia), and the other comes from ASPARTIC ACID.
There’s a similarity in the Urea formation pathway to pyrimidine synthesis. Both have a ____ source, HCO3, and _____.
Both have a NITROGEN source, HCO3, and ATP.
Carbamoyl Phosphate synthetase I has an absolute requirement for N-acetyl _______.
N-AcetylGLUTAMATE
The Urea cycle is regulated by the activation of N-acetyl glutamate synthetase via the AA ______.
ARGININE.
CPS 1 deficiency is the most severe cause for ______, whereas _____ deficiency is the most common.
Most sever cause for HYPERAMMONEMIA, whereas OtC deficiency is the most common.
Hyperammonemia can be treated with _________, which is converted to _______, and can shunt glutamine to the urine by binding it, thereby getting rid of ammonia from the body.
It can be treated with PHENYLBUTYRATE, which is converted to PHENYLACETATE, and can shunt glutamine to the urine by binding it.
