Figure 3

Effect of γ-aminobutyric acid (GABA) on apoptosis in ventilator-induced lung injury. The left lungs were isolated from rats after high-tidal-volume ventilation. The lung sections were processed for studying the changes in apoptosis by using terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) staining. (A) Shown are the representative photomicrographs (×400) of lung tissues showing TUNEL-positive cells. Apoptosis was observed in AEC II (arrow) and AEC I (arrowhead) after instillation of saline. Scale bar, 40 μm. (B) The numbers of TUNEL-positive cells were counted in 15 randomly chosen fields. The results were expressed as a percentage of that in the control animal. The total number of TUNEL-positive cells was 51.0 ± 7.9 in saline-instilled animals. Shown are the means ± SEM (n = 6 to 8 per group). *P < 0.05 versus saline; ^#P < 0.05 versus GABA.