Scotto P, Barillari R, Turek Z, Kreuzer F
Istituto di Fisiologia Umana, Univ. di Napoli, Italy.
Int J Sports Med. 1988 Apr;9(2):175-8. doi: 10.1055/s-2007-1025000.
Steady-state ventilatory response to isocapnic hypoxia was measured in awake rats: a) resident at sea level (Control); b) born at sea level and acclimatized to a simulated altitude of 3500 m (Newcomers); c) born and raised for two generations at a simulated altitude of 3500 m (HA-II Generation). Arterial PO2, PCO2, and pH were measured at the same time as ventilation. Resting ventilation (mean +/- SE) on room air in Control, Newcomers, and HA-II Generation was 707 +/- 25, 811 +/- 28 and 878 +/- 21 ml.min-1.kg-1, respectively. The ratios of ventilations measured at PaO2 55 and 100 Torr were 1.61 for Control, 1.52 for Newcomers, and 1.60 for HA-II Generation and were not significantly different from one another. The ventilatory response to 5% CO2 in air was also similar in all three groups. After four days at sea level, ventilatory responses of HA-II Generation to normoxia or isocapnic hypoxia were the same as those of sea level control. We conclude that the HA-II Generation groups had ventilatory responses to hypoxia that did not differ from those of Newcomers acclimatized to the same altitude. Unlike man, rats that were born and raised at altitude for two generations did not show any "blunting" of the ventilatory response to hypoxia.
a）居住在海平面的大鼠（对照组）；b）出生于海平面并适应模拟海拔3500米的大鼠（新适应组）；c）在模拟海拔3500米出生并饲养两代的大鼠（高海拔第二代）。在测量通气的同时测量动脉血氧分压（PO2）、二氧化碳分压（PCO2）和pH值。对照组、新适应组和高海拔第二代大鼠在室内空气中的静息通气量（平均值±标准误）分别为707±25、811±28和878±21毫升·分钟-1·千克-1。在动脉血氧分压为55和100托时测量的通气比值，对照组为1.61，新适应组为1.52，高海拔第二代为1.60，彼此之间无显著差异。三组对空气中5%二氧化碳的通气反应也相似。在海平面停留四天后，高海拔第二代对常氧或等碳酸血症性低氧的通气反应与海平面对照组相同。我们得出结论，高海拔第二代组对低氧的通气反应与适应相同海拔的新适应组没有差异。与人类不同，在高海拔出生并饲养两代的大鼠对低氧的通气反应没有表现出任何“钝化”。
