Medical Physics Laboratory, Nathan S. Kline Institute for Psychiatric Research, Orangeburg, New York; Department of Cell Biology, SUNY Downstate Health Sciences University, Brooklyn, New York.
Department of Cell Biology, SUNY Downstate Health Sciences University, Brooklyn, New York; The Robert F. Furchgott Center for Neural and Behavioral Science, SUNY Downstate Health Sciences University, Brooklyn, New York.
Biophys J. 2019 Nov 19;117(10):1783-1794. doi: 10.1016/j.bpj.2019.08.031. Epub 2019 Aug 30.
An improved version of the integrative optical imaging method has been developed that substantially increases the time resolution of diffusion measurements. We present a theory for time-resolved integrative optical imaging that incorporates a time-dependent effective diffusion coefficient in homogeneous anisotropic media and a time-dependent nonspecific linear clearance. The method was applied to measure the very fast changes in extracellular diffusion that occur during spreading depression in rat hippocampal slices. We were able to achieve a time resolution of approximately 1 s, an improvement of at least 10 times compared to the standard methods for extracellular diffusion measurement. We have found that diffusion of a small fluorescent extracellular marker (MW 3000) completely stopped during the maximum direct current shift associated with the spreading depression wave, then gradually resumed over several minutes afterward. The effect of spreading depression on extracellular space is much larger than previously estimated by other methods with lower time resolution.
一种改进的积分光学成像方法已经被开发出来，它大大提高了扩散测量的时间分辨率。我们提出了一种用于时间分辨积分光学成像的理论，该理论在各向同性均匀介质中包含了时变有效扩散系数和时变非特异性线性清除。该方法被应用于测量在大鼠海马切片中扩布性去极化期间发生的非常快速的细胞外扩散变化。我们能够实现大约 1 秒的时间分辨率，与细胞外扩散测量的标准方法相比，至少提高了 10 倍。我们发现，一种小的荧光细胞外标记物（MW 3000）的扩散在与扩布性去极化波相关的最大直流漂移期间完全停止，然后在之后的几分钟内逐渐恢复。扩布性去极化对细胞外空间的影响比以前用较低时间分辨率的其他方法估计的要大得多。
