Acute changes in the axonal cytoskeleton after mild stretching of the rat brachial plexus.
We have developed an animal model to investigate acute changes in the axonal cytoskeleton caused by a mild stretching of the peripheral nerve in the upper limbs of rats. Rat forelimbs were continuously stretched at 2 N for 1 h. Thereafter, a part of the brachial plexus and median nerve were harvested and processed for electron microscopic analysis. The total number of microtubules in the brachial plexus decreased to 55% of that of the control animals (p<0.05) without change in the number of neurofilaments. No significant changes in microtubules or neurofilaments were observed in the median nerve. By Western blotting analysis, the amount of tau protein in the stretch group significantly decreased in the brachial plexus but not in the median nerve. However, no significant changes in the amount of tubulin protein were observed in either the brachial plexus or median nerve. These results suggest that the microtubules were depolymerized by stretching of the brachial plexus and that the depolymerization may have been mediated by the decrease in the tau protein.
Kikukawa
Kenshi
K
Department of Orthopaedic Surgery, School of Medicine, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556, Japan. kikukawa-kenshi@k6.dion.ne.jp
Fukunaga
Kohji
K
Kato
Teiji
T
Yamaga
Makio
M
Miyamoto
Eishichi
E
Takagi
Katsumasa
K
D000818:Animals; D001369:Axons / Q000378:metabolism / Q000648:ultrastructure*; D001852:Bone Lengthening / Q000009:adverse effects*; D003599:Cytoskeleton / Q000378:metabolism / Q000648:ultrastructure*; D004195:Disease Models, Animal; D007124:Immunoenzyme Techniques; D008297:Male; D008475:Median Nerve / Q000293:injuries / Q000378:metabolism / Q000473:pathology*; D008870:Microtubules / Q000648:ultrastructure; D051381:Rats; D017208:Rats, Wistar; D016875:tau Proteins / Q000378:metabolism
D016875:tau Proteins