The modulation of peritoneal macrophage chemiluminescence by acute pleural inflammation, prostanoids and cyclo/lipoxygenase inhibitors.

The chemiluminescent (CL) response of peritoneal macrophages was suppressed by induction 4 h earlier of an inflammatory reaction in the pleural cavity which was negated by prior administration of indomethacin, ketoprofen and BW 755C. These changes were accompanied by a concomitant rise in peritoneal PGI2 levels which was abolished by drug pretreatment. In vitro treatment of normal peritoneal macrophages with PGI2 inhibited their subsequent CL response. Indomethacin and ketoprofen produced elevated CL of macrophages obtained from untreated controls in vitro which was blocked by the lipoxygenase inhibitor NDGA. BW 755C and NDGA in vitro strongly inhibited macrophage CL and partially inhibited CL in a cell-free system. Use of these drugs in vivo demonstrated that indomethacin and ketoprofen augmented the CL response of peritoneal macrophages while BW 755C had no effect. These results suggest the inflammatory process per se can modulate the functions of macrophages in parts of the body remote from the inflammatory site. Moreover this modulation may be under the control of the prostanoid system.