Simvastatin treatment limited VILI-associated pulmonary leukocyte infiltration. After 6 h mechanical ventilation (MV) of simvastatin (6 h Vent + Simva) or sham treated mice (6 h Vent.) and in non-ventilated sham (NV) or simvastatin (NV + Simva) treated mice, leukocytes isolated from whole left lung tissue and from blood were differentiated by flow cytometry. MV increased pulmonary PMN (a) and GR-1high monocytes (b). Simvastatin reduced PMN and monocyte counts in the lungs of ventilated mice. MV also increased circulating blood neutrophils (c) and Gr-1high monocytes (d), whereas leukocyte (e) and lymphocyte (f) counts were not significantly altered by MV (F). PMN and Gr-1high monocyte counts were higher in Simvastatin treated, ventilated mice (6 h Vent. + Simva), as compared to sham treated, ventilated mice (6 h Vent.). (a-b: NV n = 6; NV + Simva n = 7; 6 h Vent. N = 7; 6 h Vent. + Simva n = 6. c-d: NV n = 9; NV + Simva n = 9; 6 h Vent. N = 8; 6 h Vent. + Simva n = 8; *P < 0.05; **P < 0.01, ***P < 0.001).