[Correlation between the changes of oxidation reduction potential values and postmortem interval of heart blood in rabbits after death].
OBJECTIVE
To investigate correlation between the changes of oxidation reduction potential (ORP) values of heart blood in rabbits after death and postmortem interval (PMI) at different temperatures.


METHODS
Forty-eight rabbits were randomly divided into 6 groups and sacrificed by air embolism. Blood samples were taken from the right ventricle of each rabbit and stored at different temperatures of 10, 15, 20, 25, 30 and 35 degrees C, respectively. Every 4 hours from 0 h to 132 h postmortem, the ORP values of the blood samples were measured at different intervals by PB-21 electrochemical analyzer. The curvilinear regression equation was established by SPSS 17.0 software. The surface equation and 3D surface diagram were established by MATLAB 7.10.0 software.


RESULTS
The ORP values at different temperatures of heart blood in rabbits were highly correlated with the PMI. The ORP values rised obviously when the temperature was high and rised slowly when the temperature was low. The surface equation and 3D surface diagram were obtained.


CONCLUSIONS
The surface equation and 3D surface diagram of ORP values and PMI may be used for PMI estimation at different temperatures.
China University of Political Science and Law, Key Laboratory of Evidence Science, Ministry of Education, Beijing 100040, China. yangtiantong@126.com
Tian-tong
TT
Yang
School of Science, Beijing Jiaotong University, Beiing 100044, China.
Yong-guang
YG
Yu
School of Science, Beijing Jiaotong University, Beiing 100044, China.
Jing
J
Bai
China University of Political Science and Law, Key Laboratory of Evidence Science, Ministry of Education, Beijing 100040, China.
Hai-dong
HD
Zhang
Faculty of Forensic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.
Ting-yi
TY
Sun
Office of the Chief Medical Examiner of Maryland, Baltimore 21223, USA.
Mary G
MG
Ripple
Office of the Chief Medical Examiner of Maryland, Baltimore 21223, USA.
David R
DR
Fowler
China University of Political Science and Law, Key Laboratory of Evidence Science, Ministry of Education, Beijing 100040, China.
Li
L
Ling
D000818:Animals; D001769:Blood; D005260:Female; D049429:Forensic Pathology / Q000379:methods*; D006321:Heart; D008297:Male; D010084:Oxidation-Reduction; D010100:Oxygen / Q000032:analysis; D011180:Postmortem Changes; D011817:Rabbits; D012044:Regression Analysis; D013696:Temperature; D013997:Time Factors
D010100:Oxygen