抄録
Generation of subclasses of leukotrienes (LTs) from peritoneal macrophages of rat under stimulation of calcium ionophore A23187 in vitro is strongly influenced by the time elapsed after the intraperitoneal injection of thioglycollate medium. Peritoneal macrophages collected from mouse, rat, and guinea pig three days after the injection showed specific difference in the generation of LTs under the ionophore stimulation. That is, peritoneal macrophages of mouse and rat produced significant amount of LTC4 and LTB4 while those of guinea pig produced only LTB4. Enzyme solutions from macrophages of the three species converted DNCB to a colored product in the presence of glutathione, while only those of mouse and rat converted LTA4 to LTC4 in the presence of glutathione. These results suggest that macrophages of guinea pig lack “LTC4 synthetase” and also that this enzyme is different from the usual GSH Stransferases. On the basis of the enzyme activity, the subcellular distribution of LTC4 synthetase of mouse is concluded that it is present mainly in the precipitate of 105×g centrifugation. This enzyme activity can be solubilized by Triton X-100.
