Spatial heterogeneity of the axolemma of non-myelinated fibers in the optic disc of the adult rat. Freeze-fracture observations.
This freeze-fracture study examined the structure of the axolemma of non-myelinated fibers in the optic disc region of the adult rat. Spatially heterogeneous patterns of intramembranous particles (IMPs) were observed on the E-fracture faces; particle distribution patterns ranged from clusters of 4-7 IMPs to linear arrays of particles 1-3 IMPs wide that apparently encircle the axon. These bands of particles displayed a periodicity of approximately 0.16 micrometers. The present findings demonstrate that, in specialized regions, the axolemma of non-myelinated fibers not in the region of synapses can exhibit distinct spatial heterogeneity.
D000818:Animals; D001369:Axons / Q000648:ultrastructure*; D005614:Freeze Fracturing; D008566:Membranes / Q000648:ultrastructure; D008854:Microscopy, Electron; D009412:Nerve Fibers / Q000648:ultrastructure*; D009898:Optic Disk / Q000648:ultrastructure*; D051381:Rats