Title : Nitric oxide synthase activity is inducible in rat, but not rabbit alveolar macrophages, with a concomitant reduction in arginase activity - Hey_1995_Naunyn.Schmiedebergs.Arch.Pharmacol_351_651 |
Author(s) : Hey C , Wessler I , Racke K |
Ref : Naunyn Schmiedebergs Arch Pharmacol , 351 :651 , 1995 |
Abstract :
Alveolar macrophages were obtained by broncho-alveolar lavage of isolated rat and rabbit lungs and cultured (2.5 x 10(6) cells/dish) for 18 h in the absence or presence of bacterial lipopolysaccharides (LPS) alone or in combination with cytokines. Thereafter, accumulation of 3H-citrulline (NO synthase activity) and 3H-ornithine (arginase activity) were determined. During incubation of rat alveolar macrophages with 3H-arginine clear amounts of 3H-citrulline and 3H-ornithine (3.8 and 4.6% of the added 3H-arginine, respectively) were formed and most of these metabolites appeared in the incubation medium (ratios extra-/intracellular of 17 and 70 for 3H-citrulline and 3H-ornithine, respectively). When rat alveolar macrophages had been cultured with LPS the formation of 3H-citrulline was increased about 30-fold and this was accompanied by a reduction in 3H-ornithine formation of about 60%. The effects of LPS were largely attenuated by dexamethasone (10 mumol/l). Inhibition of NO synthase by NG-monomethyl-L-arginine (L-NMMA, 100 mumol/l) in LPS treated alveolar macrophages reduced the formation 3H-citrulline by more than 90% and restored the 3H-ornithine formation. After culturing in the presence of LPS the ratios extra/intracellular of 3H-citrulline and 3H-ornithine were markedly enhanced and this effect was not dexamethasone sensitive. |
PubMedSearch : Hey_1995_Naunyn.Schmiedebergs.Arch.Pharmacol_351_651 |
PubMedID: 7545789 |
Hey C, Wessler I, Racke K (1995)
Nitric oxide synthase activity is inducible in rat, but not rabbit alveolar macrophages, with a concomitant reduction in arginase activity
Naunyn Schmiedebergs Arch Pharmacol
351 :651
Hey C, Wessler I, Racke K (1995)
Naunyn Schmiedebergs Arch Pharmacol
351 :651