Structural parameters of nerve myelin.

Low-angle X-ray data from live myelinated nerve are interpreted in terms of an electron density strip model containing a total of seven parameters. Model parameters are assigned to three varieties of peripheral nerve and two kinds of central nervous system nerve. Cytoplasmic and extracellular fluid channels which occur as independent layers parallel to the plasma membrane surface are identified and described. An explanation of the Patterson function of myelinated nerve is given in terms of the proposed electron density strip model.