The Role Of Myocardiocyte Apoptosis In Dynamic Changes Of Heart Function In Septic Rats

Objective: To study the role of Fas Caspase-3 NF-kB in myocadiocyte apoptosis , and the role of myocadiocyte apoptosis in heart function change , and the clinical significance of developing changes of serum cardiac enzymes in sepsis. Methods: 60 Wistar rats were randomly divided into experimental group (n=48) and control group (n=12). The sepsis model was made by cecal ligation and puncture(CLP) in experimental group, then the rats were divided into 4 groups of 3h 5h 7h 9h after CLP(n=12 each). Without CLP control group got same treatments. Finally, following indexes were measured in each group: expression of Fas Caspase-3 NF-kB proteins in cardiac tissue ; apoptotic index(AI) of myocardiocyte; developing changes of heart function and serum cardiac enzymes. Results: (1)Indexes of heart function: There is no difference among each group in LVSP MAP (P>0.05); Compared with other groups, + LVdp/dt_max were significantly increased in CLP3h 5h 7h group(P<0.01).(2)Serum cardiac enzymes: Compared with other groups, CK CKMB were increased in each experimental group(P<0.05), AST were increased in CLP7h 9h group(P< 0.01).(3)Compared with other groups, expression of Fas Caspase-3 NF-kB protein were significant upgraded in experimental group(P<0.01), Fas Caspase-3 reached peak in CLP3h 5h group, NF-kB reached peak in CLP5h7hgroup.? Compared with control group, AI of myocardiocyte was greater in each experimental group(P< 0.01), and reached peak in CLP3h> 5h group. The result of multiple linear regression showed that expression of Fas n Caspase-3 proteins correlated with AI(P<0.01), while NF-kB donot (P > 0.05). (5) Images of myocardiocyte under light microscope: Many changes were found in experimental group, such as myocardiac tissue disordered, blood vessels hyperemia, myocardiocyte swelled or shrinked, nuclei distorted, pyknosis, karyolysis, cross striations blurred, intercalated disks disappeared; while abnormality was not found in control group. Conclusions: ? There were lots of myocardiocytes apoptosis during CLP3h-9h in septic rats, Fas -, Caspase-3- induced apoptosis maybe one of the pathways in it.?NF-KB may play a bilateral role in myocardiocyte apoptosis.d)The changes of serum myocardiac enzyme and modality of cardiac tissue suggest that myocardiocyte necrosis happened during CLP3h-9h in septic rats. DMyocardiocyte apoptosis and necrosis have different changes with the changes of heart function in sepsis, while the damage maybe covered by compensation.