哺乳动物中昼夜时间的协调
Steven M Reppert1, David R Weaver
1Department of Neurobiology, University of Massachusetts Medical School, LRB-728, 364 Plantation Street, Worcester, Massachusetts 01605, USA. steven.reppert@umassmed.edu
Nature
|August 29, 2002
概括
生物时间以循环计量,昼夜节律以24小时的尺度运行. 大脑中的一个主钟通过光线信号,在身体组织中同步分子计时机制.
科学领域:
- 时间生物学 时间生物学
- 分子生物学分子生物学
- 神经科学是一个神经科学.
背景情况:
- 生物计时包括从毫秒到几年的周期.
- 昼夜节律代表了一个经过深入研究的24小时生物定时系统.
- 分子机制在各种身体组织中驱动这些节奏.
研究的目的:
- 解释生物时间测量的基本原理.
- 强调昼夜节律在生理过程中的作用.
- 描述通过中央大脑钟对生物节奏的等级控制.
主要方法:
- 审查已建立的时代生物学研究.
- 分析不同组织中的分子时钟.
- 研究大脑的主钟功能的研究.
主要成果:
- 生物时间是通过各种循环过程来测量的.
- 循环节律是由复杂的分子机械产生.
- 大脑中的中央昼夜节律起器同步了外围时钟.
结论:
- 大脑的主钟受到光线的影响,调节周围的昼夜节律.
- 了解这些时间系统对于生理学至关重要.
- 这种等级组织确保了协调的生物功能.
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