Fiber analysis of the motor root of the mouse facial nerve.
A nerve fiber caliber analysis was performed with the electron microscope on the motor root of the facial nerve in 5 mice. The large fiber zone of the motor root contained large myelinated fibers at higher percentage than the smaller fiber zone, while the latter contained small myelinated fibers at higher percentage than the former. On the other hand, diameter frequency distribution of unmyelinated fibers did not show significant difference between the large and the small fiber zones. It is postulated that diameter frequency distribution of unmyelinated fibers may be about the same in various nerves, although that of myelinated fibers show contrast between the nerves with different functions.
D000818:Animals; D001369:Axons / Q000648:ultrastructure; D005154:Facial Nerve / Q000166:cytology*; D005260:Female; D051379:Mice / Q000033:anatomy & histology*; D008815:Mice, Inbred Strains; D008854:Microscopy, Electron; D009046:Motor Neurons / Q000166:cytology*; D009186:Myelin Sheath / Q000648:ultrastructure; D009413:Nerve Fibers, Myelinated / Q000648:ultrastructure