Formation of DNA Strand Breaks in Peripheral Lymphocytes of Rats After Exposure to Natural Sunlight  

作　　者：Dorival Mendes RODRIGUES-JUNIOR Ana Amélia de CARVALHO MELO Benedito Borges da SILVA Pedro Vitor LOPES-COSTA 

机构地区：[1]Department of Biology,Federal University of Piaui-Teresina,Piaui,Brazil [2]Department of Gynecology,Federal University of Piaui-Teresina,Piaui,Brazil

出　　处：《Biomedical and Environmental Sciences》2012年第2期245-249,共5页生物医学与环境科学（英文版）

摘　　要：Objective This paper aims to evaluate the genotoxicity in peripheral blood lymphocytes of rats after exposure to sunlight at different time points of day in a tropical region of Brazil（5oS,42oW）.Materials and Methods Thirty Wistar-Hannover rats,three months old,were randomly divided into three groups of 10 animals each：Group I [control,without exposure to ultraviolet（UV） radiation],Group II（exposed to sunlight during 08：00 a.m.to 10：00 a.m.）,and Group III（exposed to sunlight during 10：00 a.m.to 12：00 a.m.）.After a week of exposure,peripheral blood samples were taken from the tail of these animals to prepare smears on two slides per animal.In 24 h after exposure to sunlight in Group III,a new collection was obtained to observe the repair activity.The alkaline comet assay was used in this study to evaluate the genotoxic activity of sunlight（P0.05）.Results There was no statistical difference between Group I and II（P=0.672）.On the other hand,the exposure to sunlight in Group III showed genotoxic action in comparison to the other groups（P0.0001）.Also,there was no significant repair in Group III R（P=0.407）.Conclusion This study has shown a genotoxic potential of sunlight（UVA-B） in lymphocytes of mammals from 10：00 a.m.to 12：00 a.m.,due to a higher intensity of UV in this tropical region.Objective This paper aims to evaluate the genotoxicity in peripheral blood lymphocytes of rats after exposure to sunlight at different time points of day in a tropical region of Brazil（5oS,42oW）.Materials and Methods Thirty Wistar-Hannover rats,three months old,were randomly divided into three groups of 10 animals each：Group I [control,without exposure to ultraviolet（UV） radiation],Group II（exposed to sunlight during 08：00 a.m.to 10：00 a.m.）,and Group III（exposed to sunlight during 10：00 a.m.to 12：00 a.m.）.After a week of exposure,peripheral blood samples were taken from the tail of these animals to prepare smears on two slides per animal.In 24 h after exposure to sunlight in Group III,a new collection was obtained to observe the repair activity.The alkaline comet assay was used in this study to evaluate the genotoxic activity of sunlight（P0.05）.Results There was no statistical difference between Group I and II（P=0.672）.On the other hand,the exposure to sunlight in Group III showed genotoxic action in comparison to the other groups（P0.0001）.Also,there was no significant repair in Group III R（P=0.407）.Conclusion This study has shown a genotoxic potential of sunlight（UVA-B） in lymphocytes of mammals from 10：00 a.m.to 12：00 a.m.,due to a higher intensity of UV in this tropical region.

关 键 词：Comet assay DNA damage RATS SUNLIGHT Ultraviolet radiation 

分 类 号：R346[医药卫生—基础医学]