CYTOGENTIC EFFECTS OF LOW LEVEL LASER IRRADIATION OF HUMAN LEUKOCYTES

Abstract

Lasers have been applied in many aspects of medicine. In this report. the cytogenetic effects of' low power laser irradiation on the cultured human peripheral lymphocytes were studied, The lasers used are argon. He-Ne and GaAlAs diode lasers in low power density. The mitotic index, chromosomal aberrations (including chromosome or chromatid breaks and gaps) und scores for sister chromatid exchange of lymphocytes were observed. Our experiments showed that irradiation with argon laser at the dose of 30-300 J/cm² has dose-related cytostatic effects, Mitosis was inhibited completely when dose was 240 J/cm or over, There was a significant increase in the frequency of chromosome and chrematid breaks and gaps (p <0.05 with paired t-test) and also an increase of sister chromatid cxchange after 180 J/cm² (p < 0.05 with paired t-Test). As to the other lasers, there were no significant increase in the frequency of chromosome aberrations. There was an increase of mitosis after GaAlAs diode (0.5 to 1.5 J/cm²) and He-Ne laser (1 to 4J/cm²) irradiation. however, it was not significant statistically.