Biomaterial Database

Liver pathology in a new congenital disorder of urea synthesis: N-acetylglutamate synthetase deficiency. 1985

A Zimmermann, and C Bachmann, and G Schubiger

Detoxification through the urea cycle is the means by which mammalian organisms dispose of their excess ammonia. Within this cycle, N-acetylglutamate (NAG) is the most important cofactor for optimal enzyme activity. It is formed from acetyl CoA and glutamate through the action of N-acetylglutamate synthetase (NAGS). Recently, a congenital deficiency of NAGS has been reported. In this communication, we present results of structural investigations on liver tissue of the index patient with NAGS defect. Light microscopy revealed small, eosinophilic inclusions in some of the hepatocytes. Electron microscopy showed vesicular SER and fibrillar material in expanded cisterns of the RER, presumably corresponding to the inclusions seen in light microscopy. Immunofluorescence of liver tissue uncovered a discrete distribution of intracellular albumin in the form of small deposits. We suggest that in NAGS deficiency, some secretory proteins might be incompletely processed due to the lack of a protease activator, NAG.

UI	MeSH Term	Description	Entries
D007231	Infant, Newborn	An infant during the first 28 days after birth.	Neonate,Newborns,Infants, Newborn,Neonates,Newborn,Newborn Infant,Newborn Infants
D008099	Liver	A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.	Livers
D008297	Male		Males
D008661	Metabolism, Inborn Errors	Errors in metabolic processes resulting from inborn genetic mutations that are inherited or acquired in utero.	Inborn Errors of Metabolism,Metabolism Errors, Inborn,Error, Inborn Metabolism,Errors Metabolism, Inborn,Errors Metabolisms, Inborn,Errors, Inborn Metabolism,Inborn Errors Metabolism,Inborn Errors Metabolisms,Inborn Metabolism Error,Inborn Metabolism Errors,Metabolism Error, Inborn,Metabolism Inborn Error,Metabolism Inborn Errors,Metabolisms, Inborn Errors
D008854	Microscopy, Electron	Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.	Electron Microscopy
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000123	Acetyltransferases	Enzymes catalyzing the transfer of an acetyl group, usually from acetyl coenzyme A, to another compound. EC 2.3.1.	Acetyltransferase
D000641	Ammonia	A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as AMMONIUM HYDROXIDE.
D014508	Urea	A compound formed in the liver from ammonia produced by the deamination of amino acids. It is the principal end product of protein catabolism and constitutes about one half of the total urinary solids.	Basodexan,Carbamide,Carmol
D051046	Amino-Acid N-Acetyltransferase	A mitochondrial matrix enzyme that catalyzes the synthesis of L-GLUTAMATE to N-acetyl-L-glutamate in the presence of ACETYL-COA.	Acetyl CoA Glutamate N-Acetyltransferase,Acetyl Coenzyme A Glutamate N-Acetyltransferase,Amino Acid Acetyltransferase,Amino-Acid Acetyltransferase,N-Acetyl-L-Glutamate Synthetase,N-Acetylglutamate Synthase,N-Acetylglutamate Synthetase,Acetyl CoA Glutamate N Acetyltransferase,Acetyl Coenzyme A Glutamate N Acetyltransferase,Acetyltransferase, Amino Acid,Acetyltransferase, Amino-Acid,Acid Acetyltransferase, Amino,Amino Acid N Acetyltransferase,N Acetyl L Glutamate Synthetase,N Acetylglutamate Synthase,N Acetylglutamate Synthetase,N-Acetyltransferase, Amino-Acid,Synthase, N-Acetylglutamate,Synthetase, N-Acetyl-L-Glutamate,Synthetase, N-Acetylglutamate