Fig. 2. Time course of histologic injury and resolution following high lung stretch. (A ) Scatter plot representing alveolar lung tissue with sham and low-stretch ventilation, and at each time point following ventilation-induced lung injury (VILI). (B ) Scatter plot representing alveolar airspace with sham and low-stretch ventilation, and at each time point following VILI. (C–H ): Photomicrographs of representative sections of lung tissue. (C ) A sham uninjured lung, (D–H ) Lungs at 6 h, 24 h, 48 h, 96 h, and 7 days following VILI, respectively. The degree of wall thickness and inflammatory cell infiltrate is maximal at 48 h, with progressive resolution at the later time points. For sham and protective ventilated group, n = 4; for other VILI groups, n = 8; scale bar = 200 μm. * Significantly different from sham and low-stretch ventilated animals (P < 0.05, ANOVA). Sham = animals that received sham ventilation; vent = animals that received low-stretch ventilation.