X-ray Diffraction Studies on Nerve

作者：Francis O. Schmitt, Richard S. Bear, George L. Clark · 发表于：Radiology · 年份：1935 · DOI：10.1148/25.2.131 · 被引用次数：158 · 研究领域：Biofield Effects and Biophysics

FROM analysis by means of polarized light it has long been known that nerves possess a high degree of molecular organization. The axis cylinder is positively birefringent due to the presence of anisotropic material, the optic axis of which lies parallel to the long axis of the fiber. The myelin sheath is constructed of lipoid fluid crystals with optic axes perpendicular to the direction of the fiber and radially oriented (Schmidt, 18). The positive birefringence of the axis cylinder is due presumably to the protein neurofibrils which, though visible in fixed and stained preparations, have never been demonstrated in living medullated axons under physiological conditions (Peterfi, 16). In view of the success with which the x-ray diffraction method for fine-structure analysis has been applied to certain other fibrous animal tissues such as hair, chitin, connective tissue, etc., it is desirable that full use be made of this tool in the case of nerve, particularly since modern research on nerve energetics reveals that impulse propagation takes place with but extremely small initial energy liberation. Hill (11) has shown, for example, that the heat production immediately accompanying the propagated disturbance in frog nerve at room temperature is so low as to be near the limit of measurement. It seems obvious that any mechanism capable of propagating an electric potential wave at a velocity of 30 meters per second so efficiently must owe its properties in no small measure to the mo...