Control of Human Breathing in Extreme Environments

与许多通过喘气来冷却身体的小型哺乳动物不同，人类利用表面出汗作为热量损失的主要效应器。这可能令人惊讶，但人类的呼吸也会对体温的变化做出反应。热喘息响应在热时是明显的，而明显的喘息响应是冷时的特征响应。我的研究项目的主要目标是建立人体体温变化后呼吸的控制机制。我的研究假设是，高或低的体温为人类呼吸提供了重要的刺激。我的研究计划的最新进展是在三个领域。在第一个领域，我们研究了体温升高的人如何对两种呼吸气体二氧化碳和氧气的化学输入做出反应。我们确定，体温升高既独立地起作用，又与这两种呼吸气体协同作用，以控制人类呼吸。在第二个领域，我们构思、构建并验证了一种新颖的逐呼吸设备，用于精确控制两种呼吸气体。在第三个领域，类似的，明显的其他人类的体温调节热损失的反应，我们揭示了适应人类的热喘反应后，反复热应激。在拟议的研究计划中，我们将在2个研究领域采用我们的新型呼吸气体控制系统。在第一个领域，我们将确定在急性以及反复降低体温期间人类喘息反应的控制机制。在第二个领域，我们将确定如何人类热喘气反应有助于控制血压，并在老年加拿大人，我们将评估，如果这种人类热喘气适应反复热应激。这项研究对所有加拿大人的好处是提高我们对人类在极端气候下生活和提出建议的能力的理解，例如随着全球变暖，我们国家的气候变化越来越明显。

Unlike many small mammals that pant to cool their bodies, humans employ surface sweating as the main effector for heat loss. It may be surprising but human breathing also responds changes in body temperatures. Both a thermal panting response is evident in the heat and a pronounced gasp response is a characteristic response in the cold. The primary objective of my research program is to establish the mechanisms of control of human breathing after changes in body temperature. My research hypothesis is that high or low body temperatures provide an important stimulus to human breathing. Recent progress in my research program is in three areas. In the first area, we examined how humans with elevated body temperatures responded to the chemical inputs from the two respiratory gases, carbon dioxide and oxygen. We established that increased body temperature works both independently and in concert with these two respiratory gases to control human breathing. In the second area we conceived, built and validated a novel breath-by-breath device for precise control the two respiratory gases. In the third area, similar that evident for other human thermoregulatory heat loss responses, we revealed an adaptation of the human thermal panting response after repeated heat stresses. In the proposed research program, we will employ our novel control system for the respiratory gases in 2 areas of study. In the first area, we will determine the mechanism of control of the human gasp response during acute as well as repeated decreases of body temperatures. In the second area, we will ascertain how the human thermal panting response contributes the control of blood pressure, and, in elderly Canadians, we will assess if this human thermal panting adapts to repeated heat stresses. The benefits to all Canadians from this research is to improve our understanding of the human ability to live and proposer in extreme climates, such as those more and more evident in our country with global warming.