Freeze fracture analysis of the axolemma of cultured dorsal root ganglion neurons in the absence of Schwann cells

The distribution of intramembranous particles within the axolemma of cultured dorsal root ganglion neurons was determined by freeze-fracture microscopy. Utilizing culture conditions which eliminate Schwann cells, the particle distribution of the P-face, 735 +/- 119 microns2, and E-face, 100 +/- 39 microns2 resembled that of pre- and non-myelinated axons in vivo and no node-like E-face particle patching was seen. These results indicate that cultured neurite development is similar to that seen in vivo and that axons maintained in a glial-free environment do not develop nodal, E-face membrane specializations.