Thirst Deficits in Rat Model of Aging

衰老大鼠模型中的口渴缺陷

• 批准号: 7061658
• 负责人: ROBERT L THUNHORST
• 金额: $ 23.62万
• 依托单位: UNIVERSITY OF IOWA
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-06-01 至 2010-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7061658
• 关键词: age difference; aging; angiotensin II; animal old age; atrial natriuretic peptide; baroreceptors; biological models; biological signal transduction; blood chemistry; blood pressure; blood volume; body fluids; body water dehydration; homeostasis; hormone regulation /control mechanism; immunocytochemistry; juvenile animal; laboratory rat; longitudinal animal study; neural information processing; neuroregulation; osmotic pressure; renin angiotensin system; thirst; urinalysis; water drinking behavior

DESCRIPTION (provided by applicant): Dehydration involves loss of body water. Dehydration elicits reflexive and behavioral responses that slow the rate of water loss and ultimately restore body water. In order for appropriate homeostatic responses to be activated, the central nervous system must receive and integrate multiple types of sensory input from specialized receptors that monitor the status of body fluids. This afferent information includes humoral signals carried by the blood and neural signals arising from vascular receptors carried by nerves. Disturbances of water balance, including dehydration, are major health problems in the elderly. Dehydration in the elderly results from impairments in the ability of the kidney to retain water in the body, and impaired sensations of thirst. There is some understanding regarding impairments in renal and cardiovascular function in the elderly and the contributions of these mechanisms to the relative state of dehydration that is known to accompany old age. However, little is known in the elderly about control of the behavioral mechanisms that are involved in volume homeostasis. There is remarkably little knowledge about the ability of hormonal and neural signaling mechanisms to stimulate water drinking in the elderly. The present proposal builds upon the applicant's prior investigations of fluid-related afferent signaling and central processing. The proposed research will employ physiological, pharmacological, behavioral, and cellular techniques in the rat that permit the investigation of interactive hormonal (angiotensin, atrial natriuretic peptide) and neural (blood pressure/volume) afferent signals that control hypovolemic and osmotic thirst in a rat model of aging. These experiments will generate important new information about basic physiological mechanisms that maintain and restore body fluid homeostasis in aging animals. Increased understanding of these neurobiological processes will contribute to the well-being of normal individuals exposed to physiological (exercise) and environmental (heat) challenges and of certain types of patients with pathological conditions related to fluid balance (hypertension; congestive heart failure), as well as the well being of the elderly.

描述（由申请人提供）：脱水涉及体内水的流失。脱水引起反身和行为反应，这些反应减慢了水分流失的速度并最终恢复体内水。为了激活适当的稳态反应，中枢神经系统必须从监测体液状态的专用受体中接收并整合多种类型的感觉输入。这些传入信息包括由神经携带的血管受体引起的血液和神经信号所携带的体液信号。水平的干扰（包括脱水）是老年人的主要健康问题。老年人的脱水是由于肾脏在体内保留水的能力的损害以及口渴的感觉受损。人们对老年人的肾脏和心血管功能的损害以及这些机制对伴随老年脱水的相对状态的贡献有一些了解。然而，在老年人中，关于控制体内稳态涉及的行为机制的控制知之甚少。关于激素和神经信号传导机制刺激老年人饮用的能力的知识很少。本提案建立在申请人对流体相关传入信号和中央处理的先前调查的基础上。拟议的研究将在大鼠中采用生理，药理，行为和细胞技术，允许研究相互作用的激素（血管紧张素，心房纳经肽）和神经（血压/体积）的传入信号，这些信号控制着衰变大鼠模型中低伏时和渗透压。这些实验将产生有关基本生理机制的重要新信息，这些信息可以维持和恢复衰老动物中体液的体内稳态。对这些神经生物学过程的更多了解将有助于对受到生理（运动）和环境（热）挑战的正常人以及与液体平衡有关的病理状况（高血压；充血性心力衰竭）以及老年人的福祉。