Effect of electrical stimulation-induced muscle force and streptomycin treatment on muscle and trabecular bone mass in early-stage disuse musculoskeletal atrophy.
OBJECTIVE
The aim was to determine whether daily muscle electrical stimulation (ES) and streptomycin treatment would have positive or negative effects on trabecular bone mass in disuse rats.


METHODS
Seven-week-old male F344 rats were randomly divided into five groups of eight animals each: an age-matched control group (CON); a sciatic denervation group (DN); a DN + direct electrical stimulation group (DN+ES); a DN + streptomycin treatment group (DN+SM); and a DN+ES+SM group. The tibialis anterior (TA) muscles in all ES groups were stimulated with 16mA at 10Hz for 30 min/day, six days/week, for one week. Bone volume and structure were evaluated using micro-CT, and histological examinations of the tibiae were performed.


RESULTS
Direct ES significantly reduced the disuse-induced trabecular bone loss. Osteoid thickness were also significantly greater in the ES groups than in the DN group. Micro CT and histomorphological parameters were significantly lower in the DN+ES+SM group than in the DN+ES group, while there were no significant differences between the DN and DN+SM groups.


CONCLUSIONS
These results suggest that ES-induced muscle force reduced trabecular bone loss, and streptomycin treatment did not induce bone loss, but attenuated the effects of ES-induced muscle force on reducing the loss of disused bone.
Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, Japan.
H
H
Tamaki
K
K
Yotani
F
F
Ogita
K
K
Sugawara
H
H
Kirimto
H
H
Onishi
N
N
Kasuga
N
N
Yamamoto
D000818:Animals; D001842:Bone and Bones / Q000000981:diagnostic imaging / Q000187:drug effects*; D003714:Denervation; D004195:Disease Models, Animal; D004558:Electric Stimulation / Q000379:methods*; D004576:Electromyography; D008297:Male; D020966:Muscular Disorders, Atrophic / Q000000981:diagnostic imaging / Q000473:pathology*; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology*; D051381:Rats; D011916:Rats, Inbred F344; D013307:Streptomycin / Q000494:pharmacology*; D055114:X-Ray Microtomography
D011500:Protein Synthesis Inhibitors; D013307:Streptomycin