Optical Coherence Tomography Phase Measurement of Transient Changes in Squid Giant Axons During Activity
Optical Coherence Tomography Phase Measurement of Transient Changes in Squid Giant Axons During Activity
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DOI：
10.1007/s00232-009-9202-4
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发表时间：
2009-09-01
影响因子：
2.4
通讯作者：
Sivaprakasam, Aarthi
中科院分区：
文献类型：
--
作者：
Akkin, Taner;Landowne, David;Sivaprakasam, Aarthi
非接触式光学测量揭示了鱿鱼巨轴突的瞬态变化与动作电位传播有关，并在不同的环境下发生改变（即，温度）和生理（即，离子浓度）条件。使用光谱域光学相干断层扫描系统，它产生实时的横截面图像的轴突在神经腔，轴突表面沿着的深度剖面进行监测。微分相位分析显示在毫秒时间尺度上膜周围的瞬态变化，并且响应与光学测量区域处的动作电位的到达一致。冷却轴突会减慢电和光反应，并增加瞬态信号的幅度。增加浸泡轴突的NaCl浓度，其直径在高渗溶液中减小，导致动作电位传播期间的显著更大的瞬态信号。虽然观察到单相和双相行为，但双相行为主导结果。检测到的初始相位对于单个位置是恒定的，但对于不同位置是交替的;因此，在膜周围获得的这些瞬态信号似乎具有局部特征。
Noncontact optical measurements reveal that transient changes in squid giant axons are associated with action potential propagation and altered under different environmental (i.e., temperature) and physiological (i.e., ionic concentrations) conditions. Using a spectral-domain optical coherence tomography system, which produces real-time cross-sectional images of the axon in a nerve chamber, axonal surfaces along a depth profile are monitored. Differential phase analyses show transient changes around the membrane on a millisecond timescale, and the response is coincident with the arrival of the action potential at the optical measurement area. Cooling the axon slows the electrical and optical responses and increases the magnitude of the transient signals. Increasing the NaCl concentration bathing the axon, whose diameter is decreased in the hypertonic solution, results in significantly larger transient signals during action potential propagation. While monophasic and biphasic behaviors are observed, biphasic behavior dominates the results. The initial phase detected was constant for a single location but alternated for different locations; therefore, these transient signals acquired around the membrane appear to have local characteristics.