In order to analyse the macromolecular arrangment and intermolecular forces of axonfil2ament and myelin sheath, the ultrastructure of the nerve, which is immersed in isotonic NaCI aqueous solution buffered at various pH by 1/100 M. NaOH and HCJ, studied with an electronmicroscope. Toad scietic nerve is immersed in isotonic NaCI aqueous solution buff-ered at pH=2, 4.5, 7.0, 8.0, 9.0, 10.0 and 12 for 4 hours prior to fixation and is fixed by isotonic 1 % OsO4 solution buffered at each pH and is dehydrated by cold aceton. Following conclusions are obtained after careful electron-microscopies.
Morphological changes of axonfilament……Axonfilaments change morphologically very much after variation of pH of immersed solution, at pH 7.0 filaments are smooth diameter 70 to 100Å, at pH 4. 5 increased in diameter and aggregated, and at pH2 twiched and coiled. At slightly alkalic medium filament decrease in diameter and become to fine and short, and more alkalic medium than pH 10. 0 axon is filled by granules diameter 100 to 200Å.
Myelin sheath……Distinct changes on morphology of myelin sheath are not observed at nerve immersed in radium buffered at pH 4 to 9. At pH 2, slight widening of electron-dense line and seperating of lammelae at intermediate line can be observed. On other hand, at myelin sheath immersed in excelent alkalic medium (pH 12) seperating of lammelae at intermediate line and electrondense granules in this seperated lammelae can be observed.
Morphological effects of pH of immersed medium are more excessive at axonfilament thaa at myelin sheath and the formation of filaments is more contributed from ionic character of macromolecule than lammelae which make up myelin sheath. The new model of marcrom-olecular arrangement of myelin sheath is proposed from the electron microscopical studies and corespondence of this new model with X-ray diffraction patterns of nerve, electron micrographs of aceton or trypsin treated nerve and myelinogenesis are discussed.
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