Fig. 7
SN50 and TLR4 homozygous knockout inhibited endotoxin-augmented mechanical ventilation-induced caspase-3 expression and apoptosis in the diaphragm. a, b Western blots were conducted using an antibody that recognizes caspase-3 expression and an antibody that recognizes the GAPDH expression from the diaphragms of nonventilated control mice and mice ventilated at a tidal volume of 6 mL/kg or 10 mL/kg for 8 h with or without LPS administration (n = 5 per group). Arbitrary units were expressed as the ratio of cleaved caspase-3 to GAPDH (n = 5 per group). c Representative micrographs (×400) with TUNEL staining of paraffin diaphragm sections and quantification were from the diaphragms of nonventilated control mice and mice ventilated at a tidal volume of 6 mL/kg or 10 mL/kg for 8 h with or without LPS administration (n = 5 per group). SN-50 2 mg/kg was given intraperitoneally 30 min before ventilation. Apoptotic cells are identified by arrows. A bright green signal indicates positive staining of apoptotic cells, and shades of dull green signify non-reactive cells. *P < 0.05 versus the nonventilated control mice with room air; †P < 0.05 versus all other groups. Scale bars represent 20 μm. TUNEL terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling
