Gradual nerve elongation affects nerve cell bodies and neuro-muscular junctions.
The purpose of this study is to clarify the reactions of the neuro-muscular junction and nerve cell body to gradual nerve elongation. The sciatic nerves of Japanese white rabbits were lengthened by 30 mm in increments of 0.8 mm/day, 2.0 mm/day and 4.0 mm/day. A scanning electron microscopic examination showed no degenerative change at the neuro-muscular junction, even eight weeks after elongation in the 4-mm group. Hence, neuro-muscular junction is not critical for predicting damage from gradual nerve elongation. There were no axon reaction cells in the 0.8-mm group, a small amount in the 2-mm group, and a large amount in the 4-mm group. The rate of growth associated protein-43 positive nerve cells was significant in the 4-mm group. Hence, the safe speed for nerve cells appeared to be 0.8-mm/day, critical speed to be 2.0-mm/day, and dangerous speed to be 4.0-mm/day in this elongation model.
Kazuo Ikeda
K I
KI
Departments of Orthopaedic Surgery, School of Medicine, Kanazawa University, 920-8641, Kanazawa, Japan. ikeike@med.kanazawa-u.ac.jp
Masaki Matsuda
M M
MM
Daisuke Yamauchi
D Y
DY
Katsuro Tomita
K T
KT
Shigenori Tanaka
S T
ST
D000818:Animals; D019922:GAP-43 Protein / Q000378:metabolism; D008855:Microscopy, Electron, Scanning; D023421:Models, Animal; D018482:Muscle, Skeletal / Q000473:pathology; D009469:Neuromuscular Junction / Q000473:pathology / Q000502:physiology*; D009474:Neurons / Q000378:metabolism* / Q000473:pathology; D019635:Neurosurgical Procedures / Q000379:methods*; D009929:Organ Size; D011817:Rabbits; D012183:Retrograde Degeneration / Q000378:metabolism; D012584:Sciatic Nerve / Q000378:metabolism / Q000473:pathology / Q000601:surgery*
D019922:GAP-43 Protein