Arieli R, Kerem D
Undersea Biomed Res. 1984 Sep;11(3):275-85.
Laboratory white rats and fossorial mole rats (Spalax ehrenbergi) were subjected to progressive hypoxia by enclosure in a thermoregulated, confined atmosphere. Variable levels of environmental CO2 were obtained by controlling the duration of CO2 absorbance. Rats had preimplanted electroencephalographic (EEG) and electrocardiographic (EKG) electrodes and a rectal temperature probe. Animals were followed until their last gasp and EEG flattening, at which time the chamber's atmosphere was analyzed. The mole rat demonstrated a significantly lower terminal PIO2 [20.9 +/- 3.5 (SD) vs. 38.0 +/- 8.4 (SD) Torr]; however, in both animals terminal PIO2 was independent of PICO2 over a range of the latter of 0-117 Torr. Rats showed a progressive decline in rectal temperature from a PIO2 of 80 Torr on, amounting finally to 2.3 degrees C. The rats' oxygen consumption was maintained down to a PIO2 of 65 Torr and declined from then on. A group of rats with maximal CO2 accumulation showed a greater decline of rectal temperature and a steeper drop of VO2 with respect to PO2 compared to a group with no CO2 buildup. The main result was unexpected, in view of the theoretical synergism of the adverse effects of hypoxia and hypercapnia, and should reorient current thinking on survival and resuscitation in confined spaces.
将实验用白鼠和穴居鼹形鼠（斯氏鼹鼠）置于温度可控的密闭环境中，使其逐渐处于缺氧状态。通过控制二氧化碳吸收时间来获得不同水平的环境二氧化碳。白鼠预先植入了脑电图（EEG）和心电图（EKG）电极以及直肠温度探头。对动物进行跟踪观察，直至其最后喘息和脑电图平坦，此时对实验箱内的空气进行分析。鼹形鼠的终末动脉血氧分压（PIO2）显著较低[20.9±3.5（标准差）对38.0±8.4（标准差）托]；然而，在这两种动物中，在0 - 117托的二氧化碳分压（PICO2）范围内，终末PIO2与PICO2无关。白鼠的直肠温度从PIO2为80托时开始逐渐下降，最终降至2.3摄氏度。白鼠的耗氧量在PIO2降至65托之前保持稳定，之后开始下降。与一组没有二氧化碳积聚的白鼠相比，一组二氧化碳积聚最多的白鼠直肠温度下降幅度更大，耗氧量（VO2）相对于氧分压（PO2）的下降更为陡峭。鉴于缺氧和高碳酸血症不良反应的理论协同作用，这一主要结果出人意料，应该重新引导当前关于密闭空间中生存和复苏的思路。
