RESUMEN
<p><b>AIM</b>To investigate the survival rate and the level of HaCaT cells damage with ultraviolet B (UVB) radiation at various doses, and observe the protective effects of ginsenoside Rg1 and Rb1 in vitro.</p><p><b>METHODS</b>MTT assay was employed to analyze the cell survival rate after UVB radiation of 30, 60, 90 and 120 mJ x cm(-2). The damage of nucleolus and the protective effects of ginsenoside Rg1 and Rb1 were scanned by Hoechst 33258 staining and single cell gel electrophoresis assay (SCGE).</p><p><b>RESULTS</b>It was found that the cell survival rate decreased gradually and the damage of nucleolus aggravated as the radiation dose increased from 30 mJ x cm(-2) to 120 mJ x cm(-2). At the dose of 20 microg x mL(1-), obvious protective effect of ginsenoside Rg1 and Rb1 can be observed against UVB radiation-induced HaCaT cells growth inhibition and nucleolus damage.</p><p><b>CONCLUSION</b>UVB radiation inhibits HaCaT human keratinocytes growth and ginsenoside Rg1 and Rb1 can relief the damage.</p>