GaAs (904-nm) laser radiation does not affect muscle regeneration in mouse skeletal muscle.
OBJECTIVE
We evaluated the effect of GaAs (904-nm) laser, applied directly to the skin of injured muscle, in muscle regeneration.


METHODS
Muscle injury was induced in the Tibialis anterior (TA) muscle by ACL myotoxin (5 mg/kg). Two groups were irradiated with doses of 3 (n = 8) and 10 J/cm(2)(n = 8). GaAs laser (power 1.5 mW, intensity 7.5 mW/cm(2), spot 0.2 cm(2)) was applied daily for five days. Contralateral TA received a sham procedure.


RESULTS
Similar morphological aspects were found in both laser irradiated and sham muscles. No differences were found in the muscle weight, but animals irradiated with 10 J/cm(2) showed a significant gain of body weight (P = 0.002).


CONCLUSIONS
Doses of 3 and 10 J/cm(2) of GaAs laser were not efficient to promote significant morphological changes in the regenerated skeletal muscle, but the dose of 10 J/cm(2) promoted significant gain of body weight.
Master Physical Therapy Program, Universidade Federal de São Carlos, 13565-905 São Carlos, SP, Brazil.
N M
NM
Oliveira
N A
NA
Parizzotto
T F
TF
Salvini
D000818:Animals; D001152:Arsenicals / Q000494:pharmacology / Q000627:therapeutic use; D004195:Disease Models, Animal; D004307:Dose-Response Relationship, Radiation; D005708:Gallium / Q000494:pharmacology / Q000627:therapeutic use; D053685:Laser Therapy; D008297:Male; D051379:Mice; D018485:Muscle Fibers, Skeletal / Q000502:physiology; D018482:Muscle, Skeletal / Q000293:injuries / Q000473:pathology* / Q000503:physiopathology / Q000528:radiation effects*; D009929:Organ Size; D011829:Radiation Dosage; D012016:Reference Values; D012038:Regeneration / Q000528:radiation effects*
D001152:Arsenicals; C043055:gallium arsenide; D005708:Gallium