Number of TUNEL-positive and TUNEL-negative PMNs in the liver after the administration of sterile saline (□) and LPS (▩). Few TUNEL-positive and TUNEL-negative PMNs were observed in the liver after sterile saline injection. However, the number of both TUNEL-positive and TUNEL-negative PMNs increased rapidly and peaked at 6 hours after LPS injection. The percentage of TUNEL positive PMNs exceeded 50% of the total (TUNEL-positive and TUNEL-negative PMNs) at 6 hours after the LPS injection. The number of cells is expressed per mm² of TUNEL-stained paraffin sections (4 μm). Data are expressed as mean ± SD. Bars represent SD. *P < .01 versus saline treatment. Three rats per group were examined.