The effects of subthreshold electrical stimulation on apoptosis and caspase-3 expression of ischemic cardiomyocytes / 中华物理医学与康复杂志

ABSTRACT

Objective To explore the effects of electrical stimulation below the contraction threshold on apoptosis and the expression of caspase-3 in cardiomyocytes after myocardial infarction in rats.Methods Thirty-two rats were randomly divided into 4 groupsa sham-operated group,a myocardial infarction group,an ischemic electrical stimulation group and a non-ischemic electrical stimulation group.TdT-mediated X-dUTP nick end labeling (TUNEL)was used to investigate apoptosis of cardiomyocytes.Reverse transcription-polymerase chain reaction(RTPCR)and immunohistochemical techniques were used to detect the expression of caspase-3.Results ①Compared with the sham-operated group,the amount of apoptotic cardiomyocytes increased significantly in the two electrical stimulation groups and the ischemic myocardium group.Compared with the ischemic myocardium group,apoptotic cardiomyocytes decreased significantly in the two electrical stimulation groups.There was no significant difference between the two electrical stimulation groups.②Compared with the sham-operated group,in the ischemic myocardium group and the two electrical stimulation groups,expression of caspase-3 increased significantly.Compared with the ischemic myocardium group,expression of caspase-3 decreased significantly in the two electrical stimulation groups.There was again no significant difference between the two electrical stimulation groups.Conclusions Electrical stimulation below the contraction threshold can reduce ischemic cardiomyocyte apoptosis in rats.The mechanisms may be associated with down-regulation of the expression of caspase-3.Electrical stimulation below the contraction threshold of the myocardium can also reduce cardiomyocyte apoptosis in rats.