Changes of myocardial apoptosis,Bcl-2 and Caspase-3 in septic rats

Abstract

Objective To investigate myocardial apoptosis in the septic rats and to evaluate the role of Bcl-2, Caspase-3 in signal transduction of myocardial apoptosis. Methods Sixty Wistar rats were randomly divided into control group (n=30) and septic group (n=30). Either group was then divided into 5 subgroups:3 h,6 h,12 h,24 h and 36 h subgroup. Sepsis model was established by cecal ligation and puncture (CLP). Control group were given the same treatments except CLP. TUNEL method was used to determine apoptosis index (AI). Western blot was applied to determine Bcl-2 and Caspase-3 expression. Results (1) AI value increased progressively after CLP procedure and peaked at 36 h(43.742±2.495), which showed significant difference compared with control group(4.311±0.035 ). There was no significant difference between 24 h and 36 h subgroup (P>0.05). (2) Bcl-2 protein levels significantly decreased after CLP procedure compared with control group (P 0.05). Caspase-3 levels gradually increased after CLP procedure,and 36 h subgroup was the highest,but there was no significant difference between 24 h and 36 h subgroup ( P>0.05). (3) There was negative correlation between Bcl-2 and AI (r=-0.753, P<0.001). Conclusion Myocardial apoptosis may be one of mechanisms for myocardial injury in sepsis. Anti-apoptosis intervention may be a promising therapy to improve the prognosis of sepsis. Key words: Sepsis; Rat; Myocardial; Apoptosis; Bcl-2; Caspase-3