The Experimental Study Of Expression Of Connexin43 In The Models Of Psychological Stress Induced By Combined Stimuli

Objective: To investigate the expression of Cx43 in the model of psychological stress in mice, in order to provide basis for the pathologic diagnosis of sudden cardiac death caused by psychological stress. Methods: The animal model of pure psychological stress based social isolation stress, predator stress and social defeat stress was established. After the stress experiment, all the mice were received the open field test, and then the content of CRH, ACTH and CORT was detected. The pathological changes of heart were observed by Hematoxylin-eosin staining, the expression of Cx43 in myocardial tissue was measured by Immunohistochemistry,Real-time Quantitative PCR and Western Blot. Results: The activity of psychological stress group mice was reduced significantly in the open-field test, and the average content of CRH, ACTH and CORT was significantly higher than those of the normal control group. The differences were statistically significant(P<0.05). Morphological observation showed that there were no remarkable abnormities in myocardial cell observed in the psychological stress group and control group. Cx43 protein was preferentially present in the region of the intercalated disc of normal myocardium, and evenly distributed by immunohistochemistry. The expression of the Cx43 was decreased in myocardial intercalated disc of psychological stress mice, but increased in lateral myocardial cells than that of control mice and distemperedly distributed.The mean densities of Cx43 in the psychological stress group and control group were0.11±0.01 and 0.17±0.02, respectively. The differences were statistically significant in the two groups(t=10.041, P < 0.05). The levels of Cx43 protein in the psychological stress group and control group were 3.90±0.78 and 6.11±1.60,respectively. The differences were statistically significant in the two groups(P <0.05). The levels of Cx43 mRNA in the psychological stress group and control groupwere 0.33±0.24 and 0.26±0.07, respectively. The differences were no statistically significant between the two groups(T=154.00, P >0.05). Conclusion: The animal model of pure psychological stress is established with combined stress. The animal model characterized by open-field test and plasma CRH, ACTH and CORT shows the signs of psychological stress. The expression and localization of Cx43 is also significantly altered in myocardial cells of psychological stress mice.