Study on apoptosis and expression of P53, Bcl-2, bax in cardiac myocytys of congestive heart failure induced by ventricular pacing

Abstract

The apoptosis and the expression of p53, bcl-2 and Bax in myocytes of chronic rapid ventricular pacing-induced congestive heart failure (CHF) in rabbits were investigated. The CHF rabbit model (P,n=7) was established by chronic rapid ventricular pacing for 3 weeks. By using TUNEL technique the apoptosis in the myocytes in the rabbit model was studied and the expression of p53, bcl-2 and Bax in myocytes was detected by using immunohistochemical method. Sham-operated (C,n = 9) group served as control group. The results showed that there were about 4033±884. 56 apoptotic cells/10⁶ myocytes in P group, but no apoptotic cells were found in C group. Myocytes positive for p53 immunoreactivity (18.86±8.48 vs 5.06±0.87,P<0.01) and positive for Bax immunoreactivity (7. 15±1. 91 vs 0. 43±0. 09,P<0.01) were increased in P group as compared with those in C group, while the myocytes positive for bcl-2 immunoreactivity (7. 08±1.05 vs 14. 97±4.47,P< 0.01) and the ratio of bcl-2/Bax were decreased in P group as compared with those in C group. Apoptosis was involved in the development of CHF induced by continuously rapid ventricular pacing in rabbit. The expression of p53 and Bax was increased, while the expression of bcl-2 was inhibited. These might play an important role in the acceleration of the apoptosis.

Keywords

congestive heart failure / apoptosis / gene

References

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