Gravity Dependence of Otolith System Function

耳石系统功能的重力依赖性

• 批准号: 7317810
• 负责人: J David Dickman
• 金额: $ 27.86万
• 依托单位: WASHINGTON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-12-15 至 2010-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7317810
• 关键词: Acceleration; Adult; Affect; Altered Gravity; Anatomy; Behavior; Behavioral; Birds; CCR; Cell Count; Cells; Centrifugation; Characteristics; Condition; Control Animal; Coturnix japonica; Dependence; Development; Disease; Embryo; Embryonic Development; Environment; Epithelium; Exposure to; Eye; Fertilization; Fiber; Force of Gravity; Frequencies; Head; Head Movements; Hypergravity; Injury; Lead; Microgravity; Modification; Morphogenesis; Morphology; Motion; Movement; Nature; Neonatal; Numbers; Organ; Pattern; Physiological; Physiology; Principal Investigator; Property; Quail; Receptor Cell; Recovery; Reflex action; Relative (related person); Sensory; Space Flight; Stimulus; Structure; System; Testing; Time; Trauma; Treatment Protocols; Vertebrates; Week; Work; base; critical developmental period; day; design; experience; gaze; hatching; insight; macula; mature animal; nerve supply; otoconia; programs; receptor; research study; response; sensor; synaptogenesis

The primary objective of the present proposal is to determine how gravity affects the functional development of the vestibular otolith system. It is known that even moderate exposure to altered gravity conditions in adult animals can produce modifications in the anatomy, physiology, and neuromotor responses related to the vestibular system. In addition, more limited evidence shows that exposure to either microgravity or hypergravity conditions during embryogenesis and neonatal development can produce profound alterations in vestibular system structure and function. This project will compare otolith system morphology, physiology, and behavioral responses in quails that have developed from fertilization through post-hatch maturity in either Earth normal, rotational 1g, or different levels of hypergravity. The first aim is to examine and compare the distribution and type of otolith receptors and macula afferent innervation in quails raised in different gravity conditions. We predict that the number of cells and the terminal innervation patterns of afferents will increase proportionally dependent upon the force of gravity experienced during development. The second aim will examine the sensitivity, spatial tuning, and dynamic responses of otolith afferents in mature quails that have developed in different gravity conditions. The third aim will examine the effects of development in altered gravity environments upon the vestibuloocular refelex and head gaze stability in mature quails during linear motion. We hypothesize that the gaze reflex components are tuned to direct gaze behavior relative to the gravito-inertial acceleration constant experienced during development. These studies will for the first time provide basic information regarding how the presence of gravity affects the acquisition of linear motion responsiveness by receptors and primary afferents, as well as the formation of head postural stability during linear motion. This information will provide new insight into mechanisms for recovery from vestibular injury and could lead to new treatment regimens for vestibular related disease or trauma.

本提案的主要目标是确定重力如何影响功能发展 前庭耳石系统众所周知，即使是中等程度地暴露在改变的重力条件下， 成年动物可以产生与以下相关的解剖、生理和神经运动反应的改变： 前庭系统此外，更有限的证据表明，暴露于微重力或 胚胎形成和新生儿发育期间的超重力条件可产生深刻的变化， 前庭系统的结构和功能。该项目将比较耳石系统的形态，生理， 鹌鹑从受精到孵化后成熟的行为反应 无论是地球正常，旋转1g，或不同程度的超重力。第一个目的是检查和 比较不同饲养条件下鹌鹑耳石感受器和黄斑传入神经的分布和类型， 不同的重力条件。我们预测，细胞的数量和终末神经支配模式， 传入神经将根据发育期间所经历的重力成比例地增加。 第二个目标将检查耳石传入神经的敏感性、空间调谐和动态反应， 在不同重力条件下发育的成熟鹌鹑。第三个目标将研究 在重力改变的环境中对前庭眼反射和头部凝视稳定性的影响 在直线运动中的成熟鹌鹑。我们假设，凝视反射组件被调谐到直接 凝视行为相对于在发育期间经历的重力惯性加速度常数。这些 研究将首次提供有关重力的存在如何影响地球的基本信息。 通过受体和初级传入获得线性运动反应，以及形成 直线运动时头部姿势稳定性。这一信息将提供新的洞察机制， 从前庭损伤中恢复，并可能导致前庭相关疾病的新治疗方案， 外伤