Subsurface cisterna-lined axonal invaginations and double-walled vesicles at the axonal-myelin sheath interface.
The axonal-myelin sheath interface of vertebrate myelinated axons possesses special structural complexities, and there may be an intercellular macromolecular traffic transversing the periaxonal cleft that spans the internodal axon. By conventional electron microscopy and serial sectioning, we observed a category of double-walled vesicles at the axonal-myelin sheath interface, which often contained ribosome-like particles or endoplasmic reticulum. Some of them were demonstrated to continue with the subjacent axon with a thin stalk. In addition, we described a special category of axonal invaginations, probably mediated by subsurface cisternae. The functional implications of these specialized structures were discussed.
Li
Yan-Chao
YC
Department of Anatomy, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, 1110 Shimokato Tamaho-Cho, Yamanashi 409-3898, Japan. ldlyc@yahoo.com
Li
Yong-Nan
YN
Cheng
Chang-Xie
CX
Sakamoto
Hiroshi
H
Kawate
Toyoko
T
Shimada
Osamu
O
Atsumi
Saoko
S
D000200:Action Potentials / Q000502:physiology; D000818:Animals; D001369:Axons / Q000502:physiology / Q000648:ultrastructure*; D021961:Cell Membrane Structures / Q000502:physiology / Q000648:ultrastructure*; D002645:Chickens; D022162:Cytoplasmic Vesicles / Q000502:physiology / Q000648:ultrastructure; D004721:Endoplasmic Reticulum / Q000502:physiology / Q000648:ultrastructure; D046529:Microscopy, Electron, Transmission; D009046:Motor Neurons / Q000502:physiology / Q000648:ultrastructure*; D009186:Myelin Sheath / Q000502:physiology / Q000648:ultrastructure*; D012270:Ribosomes / Q000502:physiology / Q000648:ultrastructure; D013116:Spinal Cord / Q000502:physiology / Q000648:ultrastructure*