Matakas F, Birkle J, Cervós-Navarro J
Acta Neuropathol. 1978 Mar 15;41(3):207-10. doi: 10.1007/BF00690437.
Thirteen adult rabbits were exposed to a breathing air mixture containing an increasing amount of CO2 for eight weeks. When the CO2 content reached 9 Vol% the animals became apathic and lost body weight. The EEG showed a reduction of the amplitudes of 1o Hz frequences. Blood gases revealed an increase of bicarbonate but no change of pH. The blood brain barrier which was tested when the animals were killed was not disturbed. Enzyme histochemistry, light and electron microscopy revealed that moderate brain edema had occurred. From these results it is concluded that chronic hypercapnia has a hypnotic effect which in combination with chronic edema may depress vital activities considerably. However, there seem to be no irreversible morphological alterations of the brain.
13只成年兔子暴露于含有逐渐增加的二氧化碳的呼吸混合气体中达8周。当二氧化碳含量达到9%（体积分数）时，动物变得冷漠并体重减轻。脑电图显示10赫兹频率的振幅降低。血气分析显示碳酸氢盐增加但pH值无变化。在动物处死时检测的血脑屏障未受干扰。酶组织化学、光学显微镜和电子显微镜检查显示已发生中度脑水肿。从这些结果可以得出结论，慢性高碳酸血症具有催眠作用，与慢性水肿相结合可能会显著抑制生命活动。然而，大脑似乎没有不可逆的形态学改变。
