Relative levels of caspase-3 expressed in the colonic mucosa of piglets. Mucosal extracts (39 μg protein/sample) were separated by 10% SDS-polyacrylamide gel electrophoresis for determination of caspase-3 and β-actin. Values for relative caspase-3 abundance were normalized for β-actin. Data are means ± SD, n = 6. Control = piglets fed the basal diet and received intrarectal administration of sterile saline; AA = piglets fed the same control diet and received intrarectal administration of AA; NAC (AA + 500 mg/kg NAC) = piglets fed the basal diet supplemented with 500 mg/kg NAC and received intrarectal administration of AA. a, b Within the same intestinal segment, means with different superscripts differ (P < 0.05).