Arginine uptake and metabolism in cultured murine macrophages.
Transport of L-arginine and nitrite production were examined in the murine macrophage cell line J774. Lipopolysaccharide (LPS) induced a dose- and time-dependent stimulation of nitrite production which was further increased in the presence of interferon-gamma (IFN-gamma). Nitrite synthesis was dependent on extracellular arginine and inhibited in the presence of L-lysine. Treatment of cells with LPS and IFN-gamma caused a reduction in intracellular L-arginine concentration which was accompanied by increases in the levels of L-citrulline in both the cells and culture medium. These findings indicate that activation of J774 cells with LPS produces an increase in both L-arginine transport and nitrite synthesis. The elevated rate of L-arginine transport in activated J774 cells may provide a mechanism for sustained substrate supply during enhanced utilization of L-arginine for the generation of nitric oxide.
Baydoun
A R
AR
Vascular Biology Research Centre, King's College, London, UK.
Bogle
R G
RG
Pearson
J D
JD
Mann
G E
GE
D000818:Animals; D001120:Arginine / Q000378:metabolism / Q000493:pharmacokinetics*; D001692:Biological Transport; D002478:Cells, Cultured; D005109:Extracellular Matrix / Q000378:metabolism; D007424:Intracellular Fluid / Q000378:metabolism; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism*; D051379:Mice; D009569:Nitric Oxide / Q000378:metabolism; D009573:Nitrites / Q000378:metabolism
D009573:Nitrites; D009569:Nitric Oxide; D001120:Arginine