Effect of low level laser therapy on bronchial hyper-responsiveness.
The objective of this study was to investigate whether low level laser therapy (LLLT) could reduce bronchial hyper-responsiveness (BHR) induced by tumour necrosis factor-alpha (TNF-alpha) modulating the metabolism of inositol phosphate (IP) in bronchial smooth muscle cells (BSMCs). The study was on 28 Wistar rats, randomly divided into four groups. Irradiation (1.3 J/cm(2)) was administered 5 min and 4 h after bronchial smooth muscle (BSM) had been suspended in TNF-alpha baths, and the contractile response-induced calcium ion (Ca(2+)) sensitization was measured. The BSMCs were isolated, and the IP accumulation was measured before and after TNF-alpha immersion in the groups that had been irradiated or not irradiated. BSM segments significantly increased contraction 24 h after TNF-alpha immersion when exposed to carbachol (CCh) as Ca(2+), but it was significantly reduced by 64% and 30%, respectively, after laser treatment. The increase in IP accumulation induced by CCh after TNF-alpha immersion was reduced in the BSMCs by LLLT. The dose of 2.6 J/cm(2) reduced BHR and IP accumulation in the rats' inflammatory BSMCs.
Aimbire
Flávio
F
Institute of Research and Development, University of Vale do Paraíba (UNIVAP), São José dos Campos, SP, Brazil. aimbire@univap.br
de Lima
Flávia Mafra
FM
Costa
Maricilia S
MS
Albertini
Regiane
R
Correa
João Carlos
JC
Iversen
Vegard V
VV
Bjordal
Jan M
JM
D000818:Animals; D001483:Base Sequence; D016535:Bronchial Hyperreactivity / Q000139:chemically induced / Q000503:physiopathology / Q000532:radiotherapy*; D002118:Calcium / Q000378:metabolism; D002217:Carbachol / Q000494:pharmacology; D017931:DNA Primers / Q000235:genetics; D015870:Gene Expression / Q000528:radiation effects; D066298:In Vitro Techniques; D053496:Inositol 1,4,5-Trisphosphate Receptors / Q000235:genetics / Q000378:metabolism; D007295:Inositol Phosphates / Q000378:metabolism; D028022:Low-Level Light Therapy; D047028:Macrocyclic Compounds / Q000494:pharmacology; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects / Q000528:radiation effects; D032389:Myocytes, Smooth Muscle / Q000187:drug effects / Q000502:physiology / Q000528:radiation effects; D010080:Oxazoles / Q000494:pharmacology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
D017931:DNA Primers; D053496:Inositol 1,4,5-Trisphosphate Receptors; D007295:Inositol Phosphates; D047028:Macrocyclic Compounds; D010080:Oxazoles; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; C511704:xestospongin C; D002217:Carbachol; D002118:Calcium