Estudo histológico comparativo entre laser de baixa potência, própolis e associação de ambos sobre lesões de pele de Rattus norvegicus albinus

Abstract

Wound treatment involves local and systemic aspects developed by professionals from different fields, such as low power laser and propolis. The purpose of this study was to identify and histologically compare the effects of the application of 3 treatments on surgically induced skin wounds in rats: 658 nm low power laser (LPL); propolis; and LPL laser + propolis. One hundred and forty-four male Wistar albino rats (Rattus norvegicus albinus), aged 16 weeks, weighing 350-500g, from the Unifenas Central Biotherium, were used. After general anesthesia with ketamine® (ketamine hydrochloride) / Rompun® (xylazine) (0.2 mL per 100g of animal weight: 50% ketamine and 50% Rompun), the rats were shaved on the back between the shoulder blades, and then submitted to the punch excision of the skin. The animals were divided into seven groups: GL: treated with 15 mW 658 nm LPL, with radiant energy density of 3 J/cm2, with spot-type application in the center of the excision, during 3 (three), 7 (seven), 14 (fourteen) and 21 (twenty-one) consecutive days; GP5%: treated with 5% propolis; GP10%: treated with 10% propolis; GCL (Control Laser): control rats underwent the same procedures, but with the laser device off; GCP: control rats underwent the same procedures, but treated with a solution of sterile deionized water and 15% alcohol; GLP5%: treated with LPL associated with 5% propolis; GLP10%: treated with LPL associated with 10% propolis. The animals were sacrificed and histologically processed for the quantitative analysis of fibroblasts and blood vessels by means of light microscopy. Statistical tests were applied by the mean and the standard deviation in each group, based on the program SPSS 15.0, version 2007. The results showed statistical differences (Kruskal-Wallis, p≤0.01 and p≤0.05) in LPL treatment on day 3; 5% propolis treatment on day 7; LPL + 10% propolis on days 14 and 21, when compared with the other groups. No significant statistical difference was found on days 3, 7, 14 and 21 with the LPL and 5% propolis, but, when compared with the other groups, the results were significant. In face of the results, especially on days 3 and 7, both laser and propolis contributed to a faster wound healing.