Influence of the extracellular glutamate concentration on the intracellular cyst(e)ine concentration in macrophages and on the capacity to release cysteine.
Cell culture experiments with approximately physiological amino-acid concentrations show that a 3- to 5-fold elevation of the extracellular glutamate concentration causes a substantial decrease of the intracellular cysteine and glutathione content of murine peritoneal macrophages. Our experiments show, moreover, that murine peritoneal macrophages, human peripheral blood monocytes, and murine fibroblastoid cells (L-cells) consume cystine and release cysteine into the extracellular space. This process was found to be markedly suppressed in all three cell types by a 3- to 5-fold increase of the extracellular glutamate concentration. Possible implications of these effects for the pathogenetic mechanism of the acquired immunodeficiency syndrome (AIDS) are discussed.
Eck
H P
HP
Institut für Immunologie und Genetik, Deutsches Krebsforschungszentrum, Heidelberg.
Dröge
W
W
D000818:Animals; D003545:Cysteine / Q000378:metabolism*; D003553:Cystine / Q000378:metabolism; D005971:Glutamates / Q000378:metabolism / Q000494:pharmacology*; D008264:Macrophages / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D013462:Sulfur Radioisotopes; D013601:T-Lymphocytes / Q000187:drug effects / Q000378:metabolism
D005971:Glutamates; D013462:Sulfur Radioisotopes; D003553:Cystine; D003545:Cysteine