Environmental influences on fish cardiovascular function and control

环境对鱼类心血管功能和控制的影响

• 批准号: 249926-2011
• 负责人: Gamperl, Anthony
• 金额: $ 4.08万
• 依托单位: Memorial University of Newfoundland
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2014
• 资助国家: 加拿大
• 起止时间: 2014-01-01 至 2015-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=547455
• 关键词: Environmental; influences; fish; cardiovascular; function

Fish have a truly global distribution and live in waters where temperatures range from -1.8 to 42oC, that can contain little to no oxygen (i.e., are hypoxic), and may vary dramatically in salt content (e.g., estuaries). Further, human activities (including accelerated climate change) are placing added pressures on these fish, and in some areas this has lead to the displacement or extinction of species. Physiological adjustments that promote an increase in oxygen delivery to the tissues (e.g. more blood pumped by the heart, an increase in blood haemoglobin levels, adjustments in ventilation, the redistribution of blood flow) are critical if fish are to survive short- and long-term variations in these environmental variables. Indeed, it has been suggested that limitations in cardiac function as temperatures increase are a primary determinant of a fish's thermal tolerance. The proposed research will provide important insights into: 1) what factors (mechanisms) limit heart function in fishes at high temperatures; 2) interactions between the fish's immune system, stress physiology and cardiovascular function; 3) why heart function is compromised following acclimation to prolonged hypoxia; and 4) how much blood flows to the ovaries (eggs), whether it can be controlled, and how it is impacted by changes in temperature, water oxygen levels and salinity. The latter studies are important because the maintenance of oxygen and nutrient delivery to the eggs under varied environmental conditions is likely vital to ensuring that a large number of viable offspring are produced, and thus, the health of fish populations.

鱼具有真正的全球分布，在水域中的温度范围从-1.8到42oC，几乎没有氧气（即低氧），并且盐含量（例如估算值）可能会发生巨大变化。此外，人类活动（包括加速的气候变化）正在对这些鱼施加压力，在某些地区，这导致了物种的位移或灭绝。促进氧气递送到组织的生理调整（例如，心脏泵送的更多血液，血液血红蛋白水平的升高，通风的调整，血流的重新分布）至关重要），如果鱼类在这些环境变量中的短期和长期变化都至关重要。确实，已经提出，随着温度升高，心脏功能的局限性是鱼类热耐受性的主要决定因素。拟议的研究将为以下深刻的见解提供：1）在高温下，哪些因素（机制）限制了鱼类的心脏功能； 2）鱼的免疫系统，压力生理和心血管功能之间的相互作用； 3）为什么适应长期缺氧后心脏功能会受到损害； 4）多少血流流到卵巢（鸡蛋），是否可以控制，以及如何受到温度，水氧和盐度的变化的影响。后一项研究很重要，因为在不同环境条件下向卵的氧气和养分递送到卵中可能至关重要，对于确保产生大量可行的后代，因此，鱼类种群的健康状况至关重要。