家兔眼球内多因素综合评价PMI的探讨

Study on the Postmortem Interval through the Eyeballs＇ Multifactor of Rabbits

目的综合探讨死后家兔玻璃体内羟丁酸脱氢酶（HBDH）、胆碱酯酶（CHE）、谷草转氨酶（AST）、乳酸脱氢酶（LDH）四种酶的活性及角膜上皮细胞DNA含量变化与死后经过时间（postmortem interval，PMI）之间的相关性，寻求一种较准确的推断PMI的方法。方法应用全自动生化检测仪检测两组温度下（25—30℃；10—15℃）家兔死后0～54h玻璃体液四种酶失活情况以及应用计算机图像分析技术检测家兔10—15℃下死后0—72h角膜上皮细胞DNA降解情况。结果四种酶的活性在死后一定时间内各出现一个平台期，平台期后活性迅速下降。角膜上皮细胞DNA含量也随时间发生明显降解。死后玻璃体内四种酶活性及角膜上皮细胞DNA含量变化与PMI之间有显著的负相关性（P〈0．05）。结论综合死后家兔眼球内多种生化变化与PMI的多元回归方程可较准确地推断PMI。

Objective To study the correlation between the postmortem interval（PMI） and the biochemical change of rabhits＇eyeballs after death. Methods The four enzymes＇ activity of HBDH CHE Asr LDH were measured in different ambient temperatures（25 - 30℃ ; 10 - 15 ℃） of vitrous humor of rabbits in course of 0 to 54 hours after death by the colorimetric method and the DNA degradation of cornea epithelialcelison10-15℃ bythelmageCytometry. Results There was a different plateau period of the four enzymes ＇ activity in a short pefiod after death and then decreased quickly to zero after plateau period to 54 hours on 10 - 15℃ and 48 hours on 25 - 30℃ and the DNA degradation was apparent in 0- 72 hours after death. Statistically, there was a significant negative correlativity between the biochemical change and PMI（ P 〈 0.05）. Conclusion The high negative correlativity between the biochemical change of muhifactor and the postmortem interval can be comprehensively used to estimate PMI accurately.