SUBMICROSCOPIC STRUCTURE OF SINGLE NEURONS ISOLATED FROM RABBIT LATERAL VESTIBULAR NUCLEUS

Giant neurons from the lateral vestibular nuclei of rabbits have been isolated in 0.25 M sucrose by freehand dissection. They were fixed by immersion in glutaraldehyde followed by osmium tetroxide and dehydrated with Durcupan A prior to embedding in Araldite 502. By means of this simple method it was possible to achieve a preservation of isolated cells which was comparable to that obtained when small pieces of tissue are preserved, sectioned, and examined in the electron microscope. Mitochondria, however, were characterized by a condensed, granular matrix and more closely resembled those found in fractions of cells homogenized in 0.25 M sucrose than in tissue sections. Plasma membranes were essentially intact, and in fortuitous sections a trilaminar structure was demonstrated. These data support the assumption that disruption of plasma membranes and other morphological changes previously reported occur primarily after isolation of nerve cells and during their preparation for examination in the electron microscope. Although these changes could be minimized, it was difficult to estimate accurately their extent. © 1969 Academic Press, Inc.