Comparative Study on the Expression of Myocardial Connexin 43 in Different Cardioprotection Stages of Exercise Preconditioning / 中国运动医学杂志

ABSTRACT

Objective To compare the expression of myocardial connexin 43(Cx43)mRNA and its protein during early and late cardioprotection stages of exercise preconditioning.Methods Thirty-two Sprague-Dawley rats were randomly divided into a control group,an exhaustive exercise(EE)group,an early exercise preconditioning + exhaustive exercise(EEP+EE)group and a late exercise preconditioning + exhaustive exercise (LEP+EE) group,each of 8.All groups were given intervention as their group name indicated.Then in situ hybridization and real-time fluorescent quantitative PCR methods were used to detect the changes of myocardial Cx43mRNA and immunohistochemical method and Western blotting were used to detect the changes of Cx43 protein.Results Compared with EE group,there was significant increase in Cx43 mRNA and its protein expression in group EEP+EE and LEP+EE.Compared with EEP+EE group,no significant changes was found in situ hybridization and Cx43 Immunoreactivity in LEP+EE group,neither did significant differences in the expression of Cx43 mRNA and its protein.Conclusion EEP and LEP can significantly promote the expression of myocardial Cx43 mRNA and its protein respectively.However there is no significant changes of myocardial Cx43 mRNA and protein expression between the 2 time phases.It demonstrates that the expression of Cx43 in the early and late stage of myocardial protective effect was consistent with the changes of the early and late phase of the protective effect of EP.