The direct visualization of macromolecular complexes in redundant cytomembrane systems with particular reference to peripheral nerve myelin

Abstract

A combination of little used preparative techniques permits the visualization of macromolecular complexes in peripheral nerve myelin. They can be employed effectively as well for similar particulate recognition in at least some other redundant cytomembrane systems, i.e. retinal disc membranes. The cores of the globular structures are thought to be the integral proteins of the membrane system, in glutaraldehyde-fixed myelin probably associated with phospholipid annuli.Fixation is limited largely to aldehydes, with osmium tetroxide being particularly contraindicated. Cadmium ions, which form water-insoluable salts with lecithins, seem to offer some advantages when included with a glutaraldehyde fixation. Tannic acid as a secondary fixative has proven necessary when embedments are to be avoided.