Martini S, Brubakk A O, Bech C
Department of Biomedical Engineering, University of Trondheim, Norway.
Acta Physiol Scand. 1989 Mar;135(3):359-66. doi: 10.1111/j.1748-1716.1989.tb08588.x.
The ability of rats to regulate body temperature in a cool helium-oxygen (heliox) atmosphere at high pressure was studied. Thermoregulatory ability in seven awake rats was assessed in a pressure chamber at 1.5, 21 and 41 ATA by monitoring body temperature and oxygen consumption during a gradual reduction of ambient temperature. Body temperature was measured by a radiotelemetry transmitter implanted into the intraperitoneal cavity. The thermal conductance of the rats increased from 0.37 to 0.75 W kg-1 degrees C-1 as air was substituted by heliox and increased further to 1.47 and 1.81 W kg-1 degrees C-1 as the pressure was increased to 21 and 41 ATA, respectively. At high pressure the rats were able to maintain body temperature until the metabolic rate reached a value of 21.9 +/- 2.0 W kg-1, which corresponds to peak metabolic rate. This occurred at an ambient temperature of approximately 21 degrees C. Below this ambient temperature the rats did not manage to maintain body temperature. The results show that the thermal effector mechanisms of rats respond adequately to a slowly decreasing ambient temperature in hyperbaric heliox environments.
研究了大鼠在高压低温氦氧（氦氧混合气）环境中调节体温的能力。通过在压力舱内，于1.5、21和41个绝对大气压（ATA）下，在环境温度逐渐降低的过程中监测体温和氧气消耗，评估了7只清醒大鼠的体温调节能力。体温通过植入腹腔的无线电遥测发射器进行测量。随着空气被氦氧混合气取代，大鼠的热传导率从0.37增加到0.75瓦每千克摄氏度，当压力分别增加到21和41个ATA时，热传导率进一步增加到1.47和1.81瓦每千克摄氏度。在高压下，大鼠能够维持体温，直到代谢率达到21.9±2.0瓦每千克，这对应于峰值代谢率。这发生在环境温度约为21摄氏度时。低于这个环境温度，大鼠无法维持体温。结果表明，在高压氦氧混合气环境中，大鼠的热效应机制能对缓慢降低的环境温度做出充分反应。
