ObjectiveTo observe the expression of Caspase-3 mRNA in prefrontal cortex and hippocampus of chronic stress-induced depression rats,and to detect the machnisms of antidepression by electro-acupuncture.MethodsSprague-Dawley rats were randomly divided into four groups:control group,model group,model +electro-acupuncture group and model + paroxetine group,12 rats in each group.Open-field test was used to observe the changes of movements,and real-time fluorescence quantitative PCR (RT-PCR) method was used to detect Caspase-3 mRNA levels in prefrontal cortex and hippocampus.Results ①Open-field test:after stress,compared with control group rats,the model group rats' crossing numbers (29 ± 7),rearing times (6 ± 2) were apparently less than those of control group( (66 ± 13),( 10 ±2) ; P＜0.05,P＞0.05).In comparison with model group,the crossing times and rearing times being increasing in degree in electro-acupuncture group( (61 ±9),( 13 ±1 ) ) and paroxetine group( (39 ± 10),(8 ± 1 ),P＜0.01,P＞0.05).② Compared with the control group,Caspase-3 mRNA in prefrontal cortex and hippocampus significantly increased in model group(P ＜0.05 ) ;and compared with model group,Caspase-3 mRNA in prefrontal cortex in electro-acupuncture group and paroxetine group significantly decreased(P ＜ 0.05 ),and both expression of Caspase-3 mRNA in hippocampus in electro-acupuncture group and expression of Caspase-3 mRNA in hippocampus in paroxetine group decreased (P ＞ 0.05 ).ConclusionChronic stress can increase the expression of Caspase-3 mRNA in prefrontal cortex and hippocampus of chronic stress-induced depression rats,while electro-acupuncture can decrease the expression of caspase-3 mRNA,which may be an important way to anti-depression by electro-acupuncture.