Understanding the physiological factors affecting human heat dissipation

了解影响人体散热的生理因素

• 批准号: 439717-2013
• 负责人: Kenny, Glen
• 金额: $ 4.39万
• 依托单位: University of Ottawa
• 依托单位国家: 加拿大
• 项目类别: Research Tools and Instruments - Category 1 (<$150,000)
• 财政年份: 2012
• 资助国家: 加拿大
• 起止时间: 2012-01-01 至 2013-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=506218
• 关键词: Understanding; physiological; factors; affecting; human

Temperature regulation is a vital aspect of human survival as relatively small deviations in internal body (i.e. core) temperature can lead to profound disruptions in whole-body homeostasis. Prolonged exposure to hot environments and/or performing strenuous exercise can heat the body causing significant increases in internal body temperature. This heat is lost by contact with cool air and by sweat production, which cools your body as the sweat evaporates. However, when the body is unable to cool itself by sweating, several heat-induced illnesses such as heat stress or heat exhaustion and the more severe heat stroke can occur, and can result in death. Our work has demonstrated that there are a number of nonthermal factors (sensory end organs: metaboreceptors, baroreceptors, etc. and intrinsic factors: sex, aging, hydration status, fitness, etc.) that can have profound effects on the body's physiological capacity to dissipate heat. Our work is directed at understanding the separate and relative contribution of these factors during challenges to human heat balance associated with progressive elevations in environmental (elevated ambient temperature) and/or metabolic (exercise) heat load. To achieve an advanced understanding of the changes that nonthermal factors may elicit in the body's physiological capacity to dissipate, we are using the world's only whole-body calorimeter (a device for measuring heat emitted by the body) to measure how much heat the body is loosing. By understanding the precise combination of environmental and metabolic heat loads where physiological differences in the body's capacity to dissipate heat occur, we can begin to develop a better understanding of how heat stress develops. Funds obtained as part of this grant will be used to purchase research instruments that will help to maintain the operation of the world's only calorimeter (dew point mirror: used to regulate ambient humidity and measure whole-body sweating response) and increase capacity for research (laser-Doppler flowmetry: used to measure skin blood flow and therefore local heat loss).

温度调节是人类生存的一个重要方面，因为体内（即核心）温度相对较小的偏差可能会导致全身稳态的严重破坏。 长时间暴露在炎热的环境中和/或进行剧烈运动会使身体发热，导致体内温度显着升高。 这些热量通过接触冷空气和出汗而散失，汗水蒸发时，身体会变凉。 然而，当身体无法通过出汗来冷却自己时，可能会发生几种由热引起的疾病，例如热应激或热衰竭以及更严重的中暑，并可能导致死亡。 我们的工作表明，有许多非热因素（感觉末端器官：代谢感受器、压力感受器等，以及内在因素：性别、衰老、水合状态、健康等）可以对人体的生理散热能力产生深远的影响。 我们的工作旨在了解这些因素在与环境（环境温度升高）和/或代谢（运动）热负荷逐渐升高相关的人类热平衡挑战期间的单独和相对贡献。 为了深入了解非热因素可能引起人体生理耗散能力的变化，我们正在使用世界上唯一的全身热量计（一种测量身体散发热量的设备）来测量身体散失的热量。 通过了解环境和代谢热负荷的精确组合（其中身体散热能力发生生理差异），我们可以开始更好地了解热应激是如何发展的。 作为这笔赠款的一部分获得的资金将用于购买研究仪器，这些仪器将有助于维持世界上唯一的量热仪的运行（露点镜：用于调节环境湿度和测量全身出汗反应）并提高研究能力（激光多普勒流量计：用于测量皮肤血​​流，从而测量局部热量损失）。