RESUMO
OBJECTIVE@#In order to find a new parameter to estimate the postmortem interval, beta-actin mRNA in lung and thoracic muscle of rats was detected at different time point postmortem.@*METHODS@#Rats were killed by neck dislocation and left in a temperature controlling system at 21 degrees C for 12 days postmortem. Total RNA in lung and thoracic muscle at different time point was extracted and beta-actin mRNA expression was examined by RT-PCR. Semi-quantification analysis of the image of electrophoresis was performed to confirm the changes of beta-actin mRNA expression.@*RESULTS@#beta-actin mRNA in lung of rats still could be detected at 12 days postmortem, but-disappeared in thoracic muscle at 8 days postmortem.@*CONCLUSION@#The expression of beta-actin mRNA in lung and thoracic muscle could be a new parameter for estimation of PMI.