Water in Sciatic Nerve Measured by Double-Quantum-Filtered NMR

The Aims of this project is 1） to reach an understanding of factor Governing the NMR relaxation of water in peripheral nerve tissue and 2） to separate water partmentation based on parameters of H-2 double-quantum relaxation to follow "order" structure of water and to use it to unstandand physiological processed in healthy and pathological tissues.1）water in sciatic nerve of rats ：Three compartments of D12 D1H D22 D2O in anisotropic motion condition were detected by H-2 DQF NMR。The Observed Residual Quadrupole Splitting Were CA. 480、125和9赫兹在24 ° C时被分配为D12型D1 H型D22型D2 O在endoneurium、epineurium和axons相应地。三个DQF信号显示了异向性扩散，但只有轴向体部分表示的受限扩散。由于轴浆水的限制扩散，轴的内部直径估计为7.5 um.2）流动细胞型核磁共振探针的发展：我们已经制造了H-2核磁共振探针的流动细胞型。使用玻璃杯（1.5毫米内直径），科学可以在10秒内完全切换，以便我们在组织之间测量单方向水交换。3）科学神经的退化评估：水交换中的变化和H-2 DKF放松参数对Wallerian退化神经进行测量。水的渗透性增加，水结构在1-2周内被划分为3个部分。这是有可能通过H-2DQF核磁共振进行的降级过程。

The Aims of this project is 1) to reach an understanding of factors governing the NMR relaxation of water in peripheral nerve tissue and 2) to separate water compartmentation based on parameters of H-2 double-quantum relaxation to follow "order" structure of water and to use it to understand physiological processed in healthy and pathological tissues.1) Compartmentation of water in sciatic nerve of rats : Three compartments of ィイD12ィエD1HィイD22ィエD2O in anisotropic motion condition were detected by H-2 DQF NMR. The observed residual quadrupole splitting were ca. 480, 125 and 9 Hz at 24℃ which were assigned as ィイD12ィエD1HィイD22ィエD2O in endoneurium, epineurium, and axons respectively. The three DQF signals showed anisotropic diffusion, but only the axoplasm compartment represented restricted diffusion. From restricted diffusion of the axoplasm water, the inner-diameter of axon was estimated as 7.5 um.2) Development of flow-cell type NMR probe : We have made a flow-cell type of H-2 NMR probe. Using a glass capillary (1.5 mm inner diameter), perfusate of the sciatic could be switched within 10 sec which allows us to measure uni-directional water exchange between tissue compartments.3) Assessment of degeneration of sciatic nerve : Changes in water exchange and H-2 DQF relaxation parameters were measured on the Wallerian degeneration nerve. Water permeability increased and water structures in the 3 compartments degenerated by 1-2 weeks. It is possible to follow the degeneration process by H-2 DQF NMR.