RESUMEN
Although a number of ablative-laser techniques based on CO(2) and Er: YAG laser devices have been successfully developed and used in the clinical setting, the bio-molecular processes influencing wound healing after exposure to laser energy are not well elucidated. In this study, we aim to assess the impact of the mechanism of injury on the secretion of transforming growth factor beta1 (TGF-beta1) and basic fibroblast growth factor (bFGF) in various stages of wound healing, in wounds created with a CO(2) laser and scalpel. Ten Wistar rats were used to determine the levels of growth factor proteins TGF-beta1 and bFGF after CO(2) laser- and scalpel-induced skin injury. Tissue was excised on day 0 for untreated skin (control sites), and on days 1, 10, 30, and 90 following laser and scalpel surgery. Specimens were processed for histopathological analysis and for determining the concentration of growth factors by a Western blot technique. The concentration of TGF-beta1 increased markedly, at day 1 postinjury, from a baseline of 130+/-16 mm(2) (mean surface area of blotted-protein lanes) to 261+/-23 mm(2) and 394+/-22 mm(2) for laser-inflicted injury and scalpel wounds, respectively; the latter values were found to differ significantly (p<0.001). The concentration of b-FGF on day 10 postinjury differed significantly (p<0.001) between the laser sites (553+/-45 mm(2)) and the corresponding scalpel sites (418+/-41 mm(2)). Laser energy alters local tissue secretion of TGF-beta1 and bFGF of skin injuries created with the CO(2) laser compared with wounds created with a scalpel. These differences might have an impact on various aspects of wound healing of skin injuries created by a laser.
