Relationship between RNA degradation and postmortem interval in mice / 法医学杂志

ABSTRACT

OBJECTIVE@#To investigate the degradation changes of beta-actin mRNA and 18S rRNA in different time points and temperature after death, and to explore the relationship between the changes and postmortem interval (PMI) in the brain of mice.@*METHODS@#Twenty-four health adult C57BL/6 mice were randomly divided into two groups (12 each group). They were sacrificed by cervical dislocation and placed in chamber with two different temperature (4 degrees C and 37 degrees C, humidity was 80%). The mice brains were sampled at 6 different time points(immediately, 0.5h, 2h, 6h, 24h, 48h), and total brain RNA were extracted. Ct value of each sample was obtained using RT-PCR and real-time PCR technology, and beta-actin mRNA and 18S rRNA content ratio was calculated. The correlation between the content ratio and PMI was expressed using statistical regression analysis.@*RESULTS@#At 37 degrees C, RNA degradation rate was faster than 4 degrees C, which showed that there was correlation between temperature and RNA degradation. Comparing with the stability of beta-actin mRNA, 18S rRNA was more stable.@*CONCLUSION@#The study on degradation of beta-actin mRNA and 18S rRNA in mice brain using real time PCR technology could provide a new theoretical basis for estimation of PMI and would be supplementary to the traditional methods.