Urea cycle enzymes and glutamate dehydrogenase in Xenopus laevis and Bufo viridis adapted to high salinity.
Xenopus laevis was adapted stepwise to 600 m osmolar sodium chloride. After adaptation, the level of argininosuccinate lyase was raised 9-fold, carbamoylphosphate synthetase 6-fold, and ornithine carbamoyltransferase and arginase 3-fold. Liver glutamate dehydrogenase was also raised 5-fold; kidney glutamate dehydrogenase was unchanged. In Bufo viridis similarly adapted, there was a 5-fold increase in argininosuccinate lyase. When Xenopus laevis was adapted to 600 m osmolar sucrose, there was only an increase in argininosuccinate lyase, and that was only 2.4-fold. This indicates that the increases in urea cycle enzymes are at least in part responses to sodium chloride rather than just to osmotic stress.
D000222:Adaptation, Physiological; D000818:Animals; D001119:Arginase / Q000378:metabolism; D001123:Argininosuccinate Lyase / Q000378:metabolism; D002025:Bufonidae; D002222:Carbamoyl-Phosphate Synthase (Ammonia) / Q000378:metabolism; D005969:Glutamate Dehydrogenase / Q000378:metabolism*; D007668:Kidney / Q000201:enzymology*; D008099:Liver / Q000201:enzymology*; D009954:Ornithine Carbamoyltransferase / Q000378:metabolism; D012965:Sodium Chloride / Q000494:pharmacology*; D014508:Urea / Q000378:metabolism*; D014982:Xenopus laevis
D012965:Sodium Chloride; D014508:Urea; D005969:Glutamate Dehydrogenase; D009954:Ornithine Carbamoyltransferase; D001119:Arginase; D001123:Argininosuccinate Lyase; D002222:Carbamoyl-Phosphate Synthase (Ammonia)