He-Ne laser and Ga. Al. As-diode laser were irradiated at 150 to 750mJ/cm2 to cultured human vascular endothelial cells (EC) from umbilical cord vein and human fibroblasts (Fb) from human skin. He-Ne laser irradiation to EC enhanced the production of von Willebrand factor and fibronectin, while Ga. Al. As-diode laser irradiation to EC did not give a significant change. Cell growth of the Fb was not influenced significantly by both laser irradiation, but a marked decrease in the production of fibronectin was observed at as low as 150mJ/cm2 of the diode laser irradiation.
It was suggested that the effects of laser irradiation to cultured cells are different depending upon the wave length of the laser.
