DEVELOPMENT OF AUTONOMIC AND BEHAVIORAL THERMOREGULATION

自主和行为体温调节的发展

• 批准号: 2250040
• 负责人: Mark Samuel Blumberg
• 金额: $ 9.88万
• 依托单位: UNIVERSITY OF IOWA
• 依托单位国家: 美国
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-05-01 至 1999-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2250040
• 关键词: adrenal medulla; autonomic nervous system; body temperature regulation; brown fat; catecholamines; chromaffin cells; developmental neurobiology; hypoxia; innervation; laboratory rat; newborn animals; sympathetic nervous system

Mammalian thermoregulation is typically divided into two components, autonomic and behavioral. The characteristics of both components are well known in adults, but their coordination in adults makes it difficult to discern the ways in which animals integrate and coordinate responses. Developmental approaches are useful in this regard because altricial newborn mammals possess immature responses that become mature and coordinated during relatively brief developmental transitions. One such transition, recently identified in this laboratory, involves a diminution in thermoregulatory responsiveness between the ages of two and eight days. This transition is important because its occurrence suggests mechanisms of thermoregulatory activation that are different from those currently suspected. Specifically, it is believed that heat production in newborn rats is activated solely by direct neural activation of brown adipose tissue (BAT). It is hypothesized here, however, that circulating catecholamines, released from chromaffin tissue in the adrenal medulla and/or the organ of Zuckerkandl, contribute to BAT activation. It is further hypothesized that the transition from robust BAT activation at birth to muted BAT activation within one week results from developing sympathetic innervation as well as involution of the organ of Zuckerkandl. These hypotheses will be tested using pharmacological and surgical manipulations of these organs and systems during development. In parallel with these physiological investigations, a novel head-turning paradigm involving radiant heat reinforcement will be used to investigate the development of thermal preference over the same postpartum period. In addition, because a synthesis of these two approaches is one primary goal of this project, interactions between autonomic and behavioral responses will be investigated as pups develop. It is hypothesized that coordination of physiological and behavioral responses will emerge as both thermoregulatory components mature during the first week postpartum. Finally, these interdisciplinary studies of week-old rats may provide valuable information regarding the comparable developmental stage of two to four months in human infants, at which time infants are most at risk for Sudden Infant Death Syndrome.

哺乳动物的温度调节通常分为两个组成部分， 自主和行为。两个组件的特征都很好 在成年人中知道，但他们在成年人中的协调使得很难 辨别动物整合和协调反应的方式。 发展方法在这方面很有用，因为 新生儿哺乳动物具有成熟和 在相对简短的发展过渡期间协调。一个这样的 最近在该实验室中确定的过渡涉及减少 在两天到八天之间的热调节反应性中。 这种过渡很重要，因为它的发生表明了 温度调节激活与当前不同 怀疑。具体而言，据信，新生儿的热量产生 仅通过直接神经激活棕色脂肪激活大鼠 组织（蝙蝠）。但是，这里假设在循环 儿茶酚胺，从肾上腺髓质中释放 和/或Zuckerkandl的器官，有助于BAT激活。这是 进一步假设从强大的蝙蝠激活的过渡 在一周内出生静音的蝙蝠激活是由于发展而产生的 Zuckerkandl器官的同情神经和涉及。 这些假设将使用药理和外科手术进行检验 开发过程中这些器官和系统的操纵。并联 通过这些生理研究，一种新颖的型范式 涉及辐射加热的辅助将用于研究 在同一产后期间的热偏好发展。在 此外，因为这两种方法的合成是一个主要目标之一 在这个项目中，自主与行为反应之间的互动 随着幼犬的发展，将进行研究。假设协调 生理和行为反应的出现 在产后第一周，温度调节成分成熟。 最后，这些一周大鼠的跨学科研究可能会提供 有关两个的可比发育阶段的宝贵信息 在人类婴儿中到四个月，此时婴儿最有风险 对于突然的婴儿死亡综合征。