Retrospective Analysis Of 300 Cases Of Sudden Cardiac Death And Study On The Myocardial Cx43 Of Stress Effects

Objective: To summarize the 300 cases of forensic pathology cases of sudden cardiac death(SCD) characteristics. To study the expression of Cx43 and its phosphorylation in the myocardium. Methods: The cases died from cardiac sudden death of forensic pathology collected were retrospectively analyzed. According to different diagnosis of causes of death, two groups of experiment and control from the cases of submission and autopsy during 2009-2013 in Department of Forensic Pathology of Forensic Medicine, Guizhou Medical University of Science and Technology were selected.Experimental group was sudden cardiac death triggered by stress and mechanic injury was the control groups, 5 cases each and a total of 10. The expression of Cx43 protein in the myocardium was detected by the immunohistochemistry. The typical histopathological findings of stress-induced cardiomyopathy was reproduced and the plasma concentration of CA was detected in the fifth week of the experiment. The expressive level of Cx43 phosphorylation was evaluated by Western-Blot. Results: The majority of sudden cardiac death cases caused by stress(62.5%). The pathology inspection cases filing myocardial paraffin block Cx43 immunohistochemical dyeing effect were bad. After stress, the plasma CA level(36.848 + 19.89ng/L) in the stress mice was significantly higher than that(201.14 + 15.57ng/L) in the control group(P < 0.05). Conpared with the control group the Cx43 expression was found at the intercalated discs in the form of stripe with brown positive granule. Cx43 protein expression in the myocardium decreased obviously in sudden manhood death syndrome group, and some of them were distributed in the form of particle. There were similar changes in SCD group. The IODs of Cx43 in the control group, stress group, and SCD group were 26637.10±2604.98, 21711.93 ± 2844.45 and 11126.25 ± 3305.51, respectively. There weresignificant differences of Cx43 positive units in the myocardial samples among the three groups(P<0.05). The Areas of Cx43 in the control group, stress group, and SCD group were 134828.43 ± 8505.73, 117187.53 ± 13024.78 and71097.77 ± 7302.77, respectively. There were significant differences of Cx43 positive units in the myocardial samples among the three groups(P<0.05). Cx43 phosphorylation levels in the each group of myocardial were control group(476.28%±14.76%) and stress group(432.23%±25.17%) and cardiac SCD(of 188.69%±22.95%), respectively. Cx43 phosphorylation level in the three groups of myocardium showed significant difference(P < 0.05). Conclusion: Stress is an important risk factor for SCD. Specimen collection time, fixation and preservation methods of late in the forensic autopsy for detection of molecular biological index is an important influence. The absence of Cx43 expression in stress group and SCD group suggest that these cases have experienced early myocardial ischemia. Abnormal expression of distribution and state of myocardial Cx43 protein and its phosphorylation reflects the abnormal ECG activity, to diagnose and explain some sudden death(such as stress condition "negative autopsy" sudden death case) has the reference significance.