Effect of electroacupuncture on expression of hippocampal Caspase-3 in rats with cerebral ischemia/reperfusion injury

Abstract

To observe the effect of electroacupuncture (EA) on the expression level of Caspase-3, so as to explore its mechanism in inhibiting apoptosis after cerebral ischemia reperfusion. SD male rats were randomly divided into sham-operation, model, EA and Caspase-3 inhibitor groups (n=20 rats in each group). The focal cerebral ischemia/reperfusion injury rat model was established by occlusion of the middle cerebral artery. Rats of the EA group received EA at "Hegu" (LI4), "Chize" (LU5), "Zusanli" (ST36) and "Sanyinjiao" (SP6) on the affected side for 20 min. Rats of the inhibitor group were given intracerebroventricular injection of inhibitor Z-DEVD-FMK 5 μg before modeling. The neurological deficit scores (NDS) were assessed by using Longa's method, the infarct size of the brain assessed after staining with 2% triphenyltetrazolium chloride. The apoptosis index of nerve cells were observed by TUNEL staining, PCR and Western blot were used to detect the mRNA and protein expressions of Caspase-3 in the hippocampus, separately. After modeling, the NDS, infarct volume, the apoptosis index of hippocampus CA1 area, and Caspase-3 mRNA and protein expression levels were significantly increased in the model group compared with the sham-operation group (P<0.01). After intervention, the NDS, infarct volume, the apoptosis index, Caspase-3 mRNA and protein expression levels were all significantly decreased in the EA and Caspase-3 inhibitor groups re-levant to the model group (P<0.05). EA can improve the neurological function in cerebral ischemia/reperfusion rats, which may be related to its effect in inhibiting of Caspase-3 expression.