A. Time course of de novo superoxide anion generation from E. coli serotype O55:B5 LPS-stimulated rat alveolar macrophages with and without concurrent co-stimulation by hypoxia as assessed by chemiluminescence, indicating decreased de novo superoxide generation in LPS + hypoxia treated cells at t = 30 min that subsequently rebounds at t = 45 min. Open squares, LPS + hypoxia treated cells; filled squares, normoxic LPS controls; open circles, non-LPS treated hypoxic controls. * P < 0.05 vs. time-matched normoxic LPS control
B. Time course of phorbol myristate acetate (PMA) - induced chemiluminescence in LPS-stimulated rat alveolar macrophages with and without concurrent co-stimulation by hypoxia. Open squares, LPS + hypoxia treated cells; filled squares, normoxic LPS controls; open circles, non-LPS treated hypoxic controls. * P < 0.05 vs. time-matched normoxic LPS control