Koller E A, Boutellier U, Ziegler W H
Schweiz Med Wochenschr. 1983 Dec 31;113(52):1989-99.
The venous concentrations of epinephrine and norepinephrine and changes in ventilation, respiratory gases, circulation and ECG were determined in 20 young healthy male medical students during standardized stepwise ascent to 6000 m in a low pressure chamber, once without (control) and once with beta-receptor blockade (propranolol). The results show that the plasma concentration of norepinephrine increased significantly as a result of hypoxic hypoxia. The moderate increase in epinephrine was, besides the minor but significant hypoxic influence, mainly due to psychic tension. Since beta-receptor blockade does not prevent the respiratory and circulatory adjustment, beta-adrenergic stimulation is not thought to be necessary at altitude. Propranolol, on the contrary, lowers the hypoxia-induced increase in cardiac output and diminishes the ECG changes, in particular the S-T depression, significantly. By antagonizing the effects of epinephrine and by its central effects, propranolol improves subjective tolerance to altitude, and, on the other hand, by economizing the cardiac work load, the objective ability to withstand oxygen want.
在低压舱内，对20名年轻健康男性医学生进行标准化逐步升至6000米的过程中，测定了他们肾上腺素和去甲肾上腺素的静脉浓度以及通气、呼吸气体、循环和心电图的变化，一次无（对照）β受体阻滞剂，一次有β受体阻滞剂（普萘洛尔）。结果表明，低氧性缺氧导致去甲肾上腺素的血浆浓度显著升高。除了轻微但显著的低氧影响外，肾上腺素的适度升高主要归因于精神紧张。由于β受体阻滞剂并不能阻止呼吸和循环调节，因此在高原地区，β肾上腺素能刺激被认为不是必需的。相反，普萘洛尔降低了低氧诱导的心输出量增加，并显著减少了心电图变化，尤其是ST段压低。通过拮抗肾上腺素的作用及其中枢作用，普萘洛尔提高了对高原的主观耐受性，另一方面，通过节省心脏工作负荷，提高了耐受缺氧的客观能力。
