Photomedicine and Laser Surgery

Texto completo: acesso restrito. p. 767–771This article aimed to study the effect of LED Phototherapy (LED-PHT) (λ630 nm or λ850 nm) on mast cells on the dorsum of the tongue of rodents. Background Data: Vasodilatation is one of the reported effects of laser light on tissues. Laser light is able to induce the release of mediators responsible for vasodilatation, such as those produced by mast cells. Mast cells are also related to some diseases such as hay fever. Methods: Sixty Wistar rats were divided into three groups: I, Control; II, IR-LED (λ850 nm, 21.9 J/cm2, 73 sec; and III, red-LED (λ630 nm, 21.9 J/cm2, 73 sec). The specimens were taken after, 20, 45, and 60 min following irradiation. The specimens were routinely processed; stained with toluidine blue; and then total, degranulated, and non-degranulated mast cells were counted and statistical analysis performed. Results: Both LED irradiated subjects showed significant difference when compared to the control subjects on the total number mast cells (p<0.001, ANOVA), degranulated mast cells (p<0.001, ANOVA), and non-degranulated mast cells (p<0.001, ANOVA). Comparing the two groups of LED irradiated subjects, significant difference was observed regarding the total number of cells (p<0.001, paired t-test) and degranulated mast cells (p