Changes in TLR2, TLR4, TLR9, MyD88 and NF-κB protein levels on alveolar macrophages of healthy rats after 4 h of spontaneous breathing (non-ventilated) or 4 h of mechanical ventilation with tidal volumes of 7 mL/kg (low VT) or 40 mL/kg (high VT). Representative Western blot results are shown above, and quantitation of TLR2, TLR4, TLR9, MyD88 and NF-κB protein levels independent experiments is shown in (Figure 3A). Data are mean ± SD, n=10. Results were normalized to levels of GADPH protein detected on the same blots. *, P<0.001 vs. non-ventilated animals; #, P<0.001 vs. animals ventilated with low tidal volume; &, P>0.05 vs. non-ventilated animals. TLR, Toll-like receptor; MyD88, myeloid differentiation factor 88; NF-κB, nuclear factor-κB.