Estorgen Effects on Place Cells and Navigation Strategy

雌激素对位置细胞的影响和导航策略

• 批准号: 6486455
• 负责人: JENNIFER C BENNETT
• 金额: $ 0.68万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-06-20 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/6486455
• 关键词: behavior test; behavioral /social science research tag; cognition; cues; electrophysiology; estrogens; estrus; ethology; female; hippocampus; histology; hormone regulation /control mechanism; laboratory rat; memory; neural plasticity; orientation; ovariectomy; performance; predoctoral investigator; psychobiology; pyramidal cells; sex cycle; single cell analysis; stereotaxic techniques

This proposal examines estrogen effects on strategy use during spatial navigation and on hippocampal (HPC) representations of space. Estrogen (E) has been found to cause structural changes in CA1 pyramidal cells during the proestrus phase of the estrous cycle and during E treatment. Therefore, it is hypothesized that E in the HPC will result in changes in pyramidal cell electrophysiological properties, biasing the spatial navigation system for differential strategy use during high and low E conditions. To test this, spontaneous strategy use in a T-maze will be compared within animals across the estrous cycle, and between ovariectomized (OVX) and recorded and OVX with E replacement animals. Once differences in strategy use are detected, HPC CA1 place cells will be recorded while rats run on T-maze in a cue-enriched environment. Comparisons of place cell properties will initially be made between OVX and OVX+E animals and subsequently across an animal's estrous cycle. To test the stability of place cells, place field size and reliability, and responses to scrambled and novel cues are expected. This study seeks to contribute novel information on behavioral learning and memory correlates of the well-documented phenomenon of E-induced structural changes in HPC, and to provide initial data on how E affects neural representations of space in the HPC. This study has clinical relevance to the study of memory and cognitive changes associated with E loss in post-menopausal and aging women.

本研究探讨了雌激素对空间导航过程中策略使用和海马体（HPC）空间表征的影响。雌激素(E)在发情周期的发情前期和E治疗期间引起CA1锥体细胞的结构变化。因此，我们假设HPC中的E会导致锥体细胞电生理特性的变化，使空间导航系统在高E和低E条件下使用不同的策略。为了验证这一点，将在整个发情周期的动物中，以及在卵巢切除（OVX）和记录和OVX与E置换动物之间，比较t迷宫中自发策略的使用。一旦检测到策略使用的差异，当大鼠在线索丰富的环境中运行t迷宫时，HPC CA1位置细胞将被记录下来。OVX和OVX+E动物的位置细胞特性将首先进行比较，然后在动物的整个发情周期中进行比较。为了测试位置细胞的稳定性，位置场的大小和可靠性，以及对混乱和新线索的反应是预期的。本研究旨在提供行为学习和记忆相关的新信息，这些信息与已有文献记载的E诱导的HPC结构变化现象有关，并提供关于E如何影响HPC中空间的神经表征的初步数据。本研究对绝经后和老年妇女中与E丢失相关的记忆和认知变化的研究具有临床意义。