Cysteine concentration regulates cysteine metabolism to glutathione, sulfate and taurine in rat hepatocytes.

摘要: The effect of cysteine concentration and source [cysteine, methionine or 2-oxo-thiazolidine-4-carboxylate (OTC)] on the metabolism [35S]cysteine was studied in isolated rat hepatocytes. Production each major metabolites (glutathione, sulfate, taurine) increased as methionine, but not OTC, medium increased. At equimolar exogenous substrate concentrations, availability to hepatocytes greater from than that OTC. partitioning cysteine, percentage total resulting production metabolites, markedly affected by availability. Low favored its utilization for glutathione; high catabolism sulfate taurine. Under conditions low (incubations with 0.2 mmol/L OTC), glutathione, taurine accounted 90, 10 1%, respectively, metabolism. 1 + bathocuproine disulfonate), 19, 47 34%, Cysteine supplied such formed intracellularly were similarly partitioned. These studies demonstrate is a superior hepatic glutathione synthesis (presumably intracellular concentration) has sulfur