Abstract: Objective To explore whether hyperbaric oxygen(HBO) could raise the hypoxia tolerance of animals with acute mountain sickness(AMS). Methods Acute mountain sickness model was established by exposing adult Wistar mice in hypobaric chamber to observe the content of interleukin-6(IL-6) and matrix metalloproteinase-9(MMP-9) in arterial blood under the corresponding hypobaric environment. Results 1) Contents of IL-6 in model group were higher than those of control group, and the difference was statistically significant(P< 0.05); contents of IL-6 in HBO group(3 000 meters and 5 000 meters above sea level) were slightly lower than those of normal pressure oxygen(NPO) group(3 000 meters and 5 000 meters), but the difference was statistically insignificant(P>0.05). 2) Contents of MMP-9 in model group were significantly higher than those of the control group, and the difference was statistically significant(P<0.05); contents of MMP-9 in HBO group(3 000 meters and 5 000 meters) were slightly lower than those of NPO group(3 000 meters and 5 000 meters, P>0.05). Conclusion 1) The pretreatment could significantly reduce brain toxic injury of acute mountain sickness model. 2) IL-6 and MMP-9 could serve as the evaluation variables of hypoxic brain damage for AMS. 3) The HBO pretreatment regimen had no preventive effect against AMS.

Key words: hyperbaric oxygen pretreatment, acute mountain sickness animal model, interleukin-6(IL-6), matrix metalloproteinase-9(MMP-9), prevention of AMS, hypoxia tolerance