Fig. 3.
Arterial oxygen (Pao2) and carbon dioxide (Paco2) tensions of mice subjected to high tidal volume (HVT) ventilation (Fio2 0.4) in the presence and absence of various concentrations of inhaled hydrogen sulfide (H2S) (n = 6 for each concentration) or after intravascular administration of sodium sulfide (Na2S) or vehicle (n = 8 in each group). Control mice were not subjected to HVT ventilation but were briefly ventilated at tidal volume 10 ml/kg and Fio2 0.4 (n = 4). Pao2 and Paco2 were measured in arterial blood obtained from the carotid artery. Arterial oxygenation was impaired by HVT ventilation, but the decrease in Pao2 was attenuated by Na2S pretreatment. * P < 0.0001 versus control, § P = 0.0001 versus 0 ppm H2S, # P = 0.0001 versus vehicle. FIO2 = inspired oxygen fraction.