Figure 3

Comparison of macrophage-mediated bactericidal activity and intracellular NO production between control, laparotomy, and laparoscopy groups. Peritoneal macrophages were isolated from control mice (n = 28) and mice that underwent laparotomy (n = 28) or laparoscopy (n = 28). Intracellular bacterial killing by peritoneal macrophages, as represented by the bactericidal rate (%), was determined at 30 and 60 min after macrophages were chased with live E. coli (A) or S. aureus (B). Intracellular NO formation in peritoneal macrophages was detected by FACScan analysis after macrophages were incubated with culture medium (CM) and heat-killed E. coli or S. aureus for 30 min and expressed as mean channel fluorescence (MCF) per cell (C). Bactericidal rate was assessed at 60 min after peritoneal macrophages pretreated with culture medium or the iNOS inhibitor 1400 W (50 μM) for 4 h were chased with live E. coli (D). Data are mean ± SD of triplicate samples from at least four to six independent experiments. *p < 0.05 compared with control mice, ^≠p < 0.05 compared with mice that underwent laparotomy.