Bureau M, Bouverot P
Respir Physiol. 1975 Jul;24(2):203-16. doi: 10.1016/0034-5687(75)90114-0.
Awake, intact dogs trained to wear a respiratory mask were studied in a hypobaric chamber at 140 m and at various stages of a 4-week exposure to 3,550 m. Resting ventilation, pulmonary gas exchanges, arterial blood gases and pH, acid-base status of the cisternal fluid (CSF) and ventilatory responses to transient O2 inhalation were measured. Attention is focussed on the time course of ventilatory acclimatization to altitude, characterized by hyperventilation with hypocapnia and a consequent increase of arterial Po2. (1) 75 percent of the increment in pulmonary ventilation due to hypoxia was achieved in 30 minutes; (2) the further increase, 25 percent of the total hyperventilation, was complete after 3 hr, with a corresponding Pco2 drop and pH increase in blood and CSF, and an increase in Pao2; (3) the secondary increase in ventilation, beyond the acute exposure period, was not related to return of [H+] in CSF towards control value; (4) the large transient decrease of ventilation following brief oxygen inhalation demonstrated a strong arterial chemoreflex drive in acclimatized animals. The extremely rapid ventilatory acclimatization to moderately high altitude in normal dogs appears to be mediated not by CSF hydrogen ion concentration but by a strong chemoreflex drive of ventilation.
对经过训练能佩戴呼吸面罩的清醒、健康犬只，在海拔140米的低压舱以及暴露于3550米环境4周的不同阶段进行了研究。测量了静息通气、肺气体交换、动脉血气和pH值、脑池液（CSF）的酸碱状态以及对短暂吸入氧气的通气反应。重点关注通气对海拔高度适应的时间进程，其特征为伴有低碳酸血症的过度通气以及随之而来的动脉血氧分压升高。（1）由于低氧导致的肺通气增加的75%在30分钟内实现；（2）进一步增加，即总过度通气的25%，在3小时后完成，同时血液和脑脊液中的二氧化碳分压相应下降、pH值升高，动脉血氧分压增加；（3）急性暴露期过后通气的二次增加与脑脊液中[H⁺]恢复至对照值无关；（4）短暂吸入氧气后通气的大幅短暂下降表明适应环境的动物存在强烈的动脉化学反射驱动。正常犬只对中等高度海拔的通气适应极快，这似乎不是由脑脊液氢离子浓度介导的，而是由强烈的通气化学反射驱动介导的。
