title: Extracellular matrix metabolism by chondrocytes. 4. Role of glutamine in glycosaminoglycan synthesis in vitro by chondrocytes.
abstract: The rate of synthesis of glycosaminoglycans by cartilage was shown to be dependent on an exogenous source of L-glutamine. In the absence of L-glutamine the tissue and cellular levels of this amino acid were rapidly depleted. The levels of nucleotide sugars and their precursors were measured after separation on Dowex 1 (formate form) in cartilage incubated with and without L-glutamine. It was found that the levels of N-acetylhexoamine 6-phosphate and UDP-N-acetylhexosamine were decreased by 27 and 40% respectively. This demonstrates that L-glutamine is required as the amido group donor in the synthesis of glucosamine 6-phosphate and that the decrease in glycosaminoglycan synthesis is due to the limitation in synthesis of UDP-N-acetylhexoamine.
mesh_terms: D000818:Animals; D002358:Cartilage, Articular / Q000378:metabolism*; D002645:Chickens; D005973:Glutamine / Q000378:metabolism*; D006025:Glycosaminoglycans / Q000096:biosynthesis*; D007700:Kinetics; D008297:Male; D014539:Uridine Diphosphate Sugars / Q000378:metabolism
chemical_list: D006025:Glycosaminoglycans; D014539:Uridine Diphosphate Sugars; D005973:Glutamine