Effect of pulsed ultrasound of low intensity in L929 fibroblastic cultures

Abstract

The ultrasound, commonly used in physiotherapy, is considered an important therapeutic resource to musculoskeletal disorders. In this study, it is analyzed the cellular response after ultrasonic radiation pulses of low intensity in fibroblast cell culture. It was applied a culture of L929 fibroblastic cells, radiated with ultrasound pulse of low intensity, divided into six groups: I – control (which did not receive radiation), II – 0.2 W/cm2, III – 0.6 W/cm2, IV – 0.8 W/cm2, V – 1.0 W/cm2 and VI – 2.0 W/cm2. The radiation occurred during four days with intervals of 24 hours. After each interval, the cultures were analyzed by the method of MTT 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyl tetrazolium bromide. The results showed that the effect of 0.6 W/cm2 pulsed ultrasound of 10% was statistically significant compared to pulsed ultrasonic irradiation of 20% (p < 0.05). According to the parameters used in radiation of fibroblasts culture, it was concluded that both the system of control of the pulse as the intensity employed are necessary to make a better use of ultrasound therapy, since the low and medium intensity reduce the damage cell.