Hughes M J, Kopetzky M T, Messiha F, Light K, Barnes C D
J Appl Physiol Respir Environ Exerc Physiol. 1981 Dec;51(6):1607-11. doi: 10.1152/jappl.1981.51.6.1607.
To test the hypothesis that acclimation to simulated high altitude (SHA) may occur in the tissues as well as in the systemic regulatory apparatus of an organism, atria isolated from young rats acclimated to SHA of 6,000 m and from control rats were observed under normoxic conditions. SHA atria have slower spontaneous heart rates than atria isolated from controls (209 +/- 4 vs. 228 +/- 3, P less than 0.001). SHA atria are more sensitive to pentobarbital sodium (P less than 0.001) and ethanol (P less than 0.06): spontaneous mechanical activity stops at a lower drug concentration in SHA than in control atria. SHA atria are less sensitive to norepinephrine in the concentration range of 7.9 X 10(-9) to 3.1 X 10(-6) M and respond to increased bath concentrations (3.8, 5.8 and 7.8 mM) of calcium with a significantly (P less than 0.04) smaller chronotropic response and a greater inotropic response than atria from control animals. These data support the above-mentioned hypothesis.
为了验证生物的组织以及全身调节系统可能会出现对模拟高海拔（SHA）的适应性这一假设，对从适应6000米SHA的幼鼠和对照幼鼠分离出的心房在常氧条件下进行了观察。与从对照动物分离出的心房相比，适应SHA的心房自发心率较慢（209±4对228±3，P<0.001）。适应SHA的心房对戊巴比妥钠（P<0.001）和乙醇（P<0.06）更敏感：在较低的药物浓度下，适应SHA的心房的自发机械活动就会停止，而对照心房则不然。在7.9×10⁻⁹至3.1×10⁻⁶M的浓度范围内，适应SHA的心房对去甲肾上腺素的敏感性较低，并且与对照动物的心房相比，在浴液钙浓度增加（3.8、5.8和7.8 mM）时，其变时反应明显较小（P<0.04），而变力反应更大。这些数据支持上述假设。
