mRNA NGAL levels were determined in the (A-C) liver, (D, E) kidney, (F-H) lung, and (I-K) spleen in normal (unmanipulated) mice, and 4 and 24 hours after sham, AKI or BNx in wild type (WT) and IL-6−/− mice. N=3 to 12 mice per group from 3 experiments. Results are expressed as mean ±SEM and analyzed by t test: WT versus IL-6−/− at the same time point (indicated above the bar) and versus normal WT (indicated below the bar: *P<0.05; **P<0.01, ***P < 0.0001).