Figure 4

Gene transfer of β2 or β3 subunits of the Na⁺,K⁺-ATPase into mouse lungs with existing LPS-induced injury failed to reduce lung edema. Lung injury was established in C57B6 mice (n = 9) by aspiration of LPS (5 mg/kg) and 1 day later plasmids (100 μg each) expressing either no insert (pcDNA3), the β1, β2, or β3 subunits of the Na⁺,K⁺-ATPase (β1, β2, or β3) were delivered in 50 μl to the lungs by aspiration followed immediately by electroporation. Two days later, wet to dry ratios were determined as a measure of pulmonary edema fluid and shown as mean ± SEM. All experiments were carried out three times and a representative experiment is shown. One-way ANOVA with post-hoc Tukey’s multiple comparisons was used for statistical analysis; a, p < 0.0001 compared to naïve; b, p < 0.05 compared to LPS alone; c, p < 0.01 compared to LPS + pcDNA3; d, p < 0.05 compared to LPS + β1.