应用单细胞凝胶电泳检测大鼠死后脾细胞核DNA降解与死亡时间的关系

目的:探讨应用单细胞凝胶电泳技术(SCGE)检测大鼠死后脾细胞核DNA降解与死亡时间的一般规律,为早期死亡时间的推断提供新的方法。方法:建立大鼠死亡模型,在死后27h内,每隔3h取脾组织样本进行单细胞凝胶电泳,用共聚焦显微镜摄取彗星图像,应用彗星图像分析软件(IMI1.0)进行图像分析,并作统计学分析。结果:大鼠死后,脾细胞在电泳图像上出现了明显的彗星形拖尾,其尾长(TL)、尾矩(TM)在一定的时间范围内(0～15h)随死亡时间的延长而逐渐增大,二者均与死亡时间(PMI)呈现一定的相关回归关系。结果:单细胞凝胶电泳技术可应用于早期死亡时间的推断;彗星图像分析软件为SCGE的结果分析提供了便利。

Relationship between Nuclear DNA Degradation of the Rat's Spleen Cells and Postmortem Interval Assayed by Single Cell Gel Electrophoresis

Objective: To explore the regulation of the spleen nuclear DNA degradation in rats after death by single cell gel electrophoresis(SCGE) and to provide a new method for the estimation of early postmortem interval. Methods: A rat death model was established. The samples of spleen were taken at 3-hour-interval within 27 hours after the rat's death. After single cell gel electrophoresis, the comet images were recorded by the confocal microscope and analyzed by SCGE image analysis software (IMI1.0). Results: An evident comet tail was observed after electrophoresis. The tail length and the tail moment increased with an increased postmortem interval (PMI, 0~15 h), which was statistically correlated with PMI. Conclusion: Exploring the regulation of DNA degradation by single cell gel electrophoresis may be used as a predictor of early postmortem interval and the image analysis software was a good tool for SCGE comet analysis.