Abstract: Objective To observe cardiac ultrastructure and the expression of heat shock protein 70 （HSP70） and hypoxia inducible factor-1α （HIF-1α） in electric shock death rats and to explore the application of these indexes as the basis of medical identification in electric shock death. Methods Seventy-two SD rats were randomly divided into electric shock death group, postmortem electric shock group and the control group. The changes of myocardial ultrastructure were observed by transmission electron microscope, and the expressions of myocardial HSP70 and HIF-1α were observed by immunohistochemical technology. Results Myocardial myofibril fracture, mitochondrial cristae and membrane dissolution, and disordered arrangement of Z lines and M lines were observed in electric shock rats. HSP70 and HIF-1α were strong positive expressions in the electric shock death group, significantly compared with the control and postmortem electric shock groups （P<0.05）. Conclusion The expressions of HSP70 and HIF-1α were obviously increased in electric shock death group, which may be used as the diagnostic indicator of electric shock death.

Key words:  forensic pathology, electric injuries, heart, heat shock protein 70 （HSP70）, hypoxia inducible factor-1&alpha, （HIF-1α）, rats