ABSTRACT
Objective: To investigate the changes of cardiac sympathetic nerve function and susceptibility of ventricular arrhythmia at chronic stress condition in experimental rats. Methods: A total of 30 SD rats were randomly assigned into two groups: Control group, the rats were fed with normal condition and Chronic stress group, the rats were fed with unpredictable chronic stimulus program.n=15 in each group and all animals were treated for 4 weeks. The behavior of rats was assessed by open ifeld test and sucrose intake test, the susceptibility of ventricular arrhythmia was measured by Burst stimulus program under narcosis condition, and the sign of cardiac sympathetic nerve reconstruction, tyrosine hydroxylase content was examined by immunohistochemistry. Results: Compared with Control group, Chronic stress group had decreased ratio of sucrose favorite/open field test, P0.05. Immunohistochemistry presented that Chronic stress group had much higher tyrosine hydroxylase content (1397.8 ± 268.8) um2/mm2 than Control group (995 ± 232.3) um2/mm2,P Conclusion: Chronic stress may increase the susceptibility of ventricular arrhythmia in experimental rats, and the cardiac sympathetic nerve reconstruction might be an important mechanism.