Kinetics of oxygen metabolism indices in the course of histamine secretion from rat mast cells.

In this study data are presented on the kinetics of changes in malondialdehyde content (MDA), lipoxygenase activity (LO), superoxide dismutase activity (SOD), glutathione peroxidase activity (GSH-Px) and glutathione reductase activity (GSSG-Red) during the course of histamine secretion from rat mast cells. Both receptor-mediated (antigen, polymyxin B, compound 48/80) and non-receptor (the calcium ionophore A23187) stimuli of mast cell activation were investigated. A similar alteration in all the studied indices was observed after challenge with receptor-mediated stimuli. The earliest event was a decrease in SOD-activity, which coincided with the increase in histamine secretion. SOD-activity then gradually increased above the baseline levels. Similar changes in GSSG-Red- and GSH-Px-activities were also observed. The increase in MDA content occurred slightly later. Challenge with the calcium ionophore A 23187 did not cause a reduction in SOD-activity, only the increase in activity was observed. Histamine release induced by all stimuli was accompanied by a marked elevation in enzymatic peroxidation (LO-activity). Diethyldithiocarbamate (DTC), which inhibits SOD, not only blocked the enzyme activity but also caused a dose-dependent inhibition of histamine release and an inhibition of the elevation of enzymatic peroxidation in mast cells challenged with compound 48/80.