EFFECTS OF EXERCISE AT HIGH ALTITUDE ON CARDIOPULMONARY FUNCTION

1)高原运动对心肺功能的影响为探讨世代居住在高原的藏族人氧转运功能的差异，对17名高原藏族人和19名海拔3417米的汉族人进行了运动时的呼吸、循环、代谢和气体交换功能的测定。在最大努力下，藏族人比汉族人表现出更高的耗氧量、每搏量、心输出量和最大通气量。藏族的绝对耗氧量无氧阈值较高，汉族的无氧阈值较高。我们的结论是，长期暴露在低氧环境中，导致了氧气转运的增加和有氧运动能力的提高。b)研究了终身藏族青少年和适应高原的汉族新移民青少年氧气转运的差异。我们发现，从出生到青春期一直暴露在高海拔环境中会导致EF…更充足的氧气运输和更好的有氧运动能力，这可能反映了对高原生活的成功适应2)高原肺水肿的病理生理学我们先前已经证明，高原肺水肿易感性受试者(高原-S)对低氧有明显的肺血管反应。本文探讨了高原肺心病患者和健康对照组血浆内皮素-1水平与急性缺氧性肺血管反应的关系。2)对4例HAPE患者的肺泡灌洗液中细胞因子进行检测，发现IL-1、IL-6、II-8和TNFa水平显著升高，但恢复后很快恢复到正常范围或未检测到。IL-1α、IL-10和P-选择素水平无明显变化。这些结果表明，HAPE可能会发生几乎与ARDS相同的炎症过程，但这些变化是暂时的。c)我们用放射性同位素核素扫描检测了HAPE易感受试者的肺血流动力学反应。我们进行了通气-灌注显像，获得了Q-V和V/Q的功能图像。在功能图像上，低氧时肺血流从下肺野明显移至UPP肺野，而HAPE易感者的局部通气量无明显变化。D)我们研究了人类白细胞抗原DR-6是否是HAPE的遗传易感因素。在HAPE易感人群中，DR-6的频率增加，这表明他们在肺循环和对低氧和缺氧的呼吸反应中存在结构性异常，遗传因素可能参与了HAPE的发生。较少

1) EFFECTS OF EXERCISE AT HIGH ALTITUDE ON CARDIOPULMONARY FUNCTIONa) To examine the difference for oxygen transport between Tibetan living for generations at high altitude a acclimatized Han newcomers to high altitude, we measured the ventilatory, circulatory, metabolic and gas exchanges function during exercise in 17 Tibetans and 19 Hans at the altitude of 3417m in China. At maximal effort, the Tibetans, compared with the Hans, showed higher O2 consumption, stroke volume, cardiac output, and the maximal ventilation. The anaerobic threshold for absolute O2 consumption for the Tibetan are highent for the Hans. We conclude that the lifelong exposure to an hypoxic environment has resulted in an increase in oxygen transport and improved aerobic exercise performance.b) The difference of oxygen transport between adolescents of lifelong Tibetans and acclimatized Han newcomers to high altitude was studied. We found that the exposure to high altitude from birth to adolescence resulted in an ef … More ficient oxygen transport and a greater aerobic exercise performance which may reflect a successful adaptation to life at high altitude.2) PATHOPHYSIOLOGY OF HIGH ALTITUDE PULMONARY EDEMAa) We have previously shown that high altitude pulmonary edema-susceptible subjects (HAPE-S) have an accentuated pulmonary vascular response to hypoxia. We investigated the relationship between plasma endothelin-1 levels and the acute hypoxic pulmonary vascular response in patients with HAPE-S and healthy control subjects. We found that the increased pulmonary vascular response to acute hypoxia in HAPE-S may n related to endothelin-1 release.b) The cytokines were measured in the bronchoalveolar lavage fluid from four patients with HAPE.The leves IL-1*IL-6, II-8, and TNFalpha were considerably increased but returned quickly to the normal ranges or wel not detected after recovery. The levels of IL-1alpha, IL-10, and P-selectinlevels didi not change. These rest suggest that an inflammatory process almost identical with ARDS may occur in HAPE,but that these changes transient.c) We examined the pulmonary hemodynamic response to hypoxia in HAPE susceptible subjects by radioisotop scintigraphy. We performed ventilation-perfusion scintigraphyand acquired functional images of Q V and V/Q the functional images, the pulmonary blood flow was significantly shifted from the lower lung field to the upp lung field under hypoxia but no significant change of regional ventilation was observed in the HAPE-susceptibl subjects. As a results, they showed ventilation-perfusion mismatch.d) We studied whether human leukocyte antigen DR-6 functions as agenetic predisposition to HAPE.The frequency of DR-6 was increased in the subjects susceptible to HAPE,which suggests that they have a constitutional abnormality in the pulmonary circulatory, and ventilatory responses to hypoxia and hyhobaria, and that genetic factors may be involved in the development of HAPE. Less