Objective To explore the effects and potential mechanism of electroacupuncture at acute phase on cognitive dysfunction at later stage in rats with middle cerebral artery occlusion(MCAO).Methods Totally 39 SD rats were randomly divided into sham-operation group,model group and electroacupuncture group,with 13 rats in each group.MCAO model was established by Zea Longa thread embolism method in model group and electroacupuncture group.The sham-operation group only separated blood vessels.Electroacupuncture group was treated with electroacupuncture at"Baihui"and"Shenting"acupoints at 5 min and 6 h after model establishment respectively,for 30 min.The body mass,modified neuropathy severity scale(mNSS),and percentage of stiff immobility time of rats were monitored weekly,Nissl staining was used to observe the morphology of hippocampal tissue on the 28 d,immunofluorescence staining was used to detect the expression of Ki67,dual cortin(DCX)and neuronal differentiation factor 1(NeuroD1)in dentate gyrus of the hippocampus,the expression of synaptic vesicle protein 2A(SV2A)protein in dentate gyrus of hippocampus was detected by Western blot.Results Compared with the sham-operation group,on the first day after operation,the body mass of the model group rats decreased,then gradually increased,and on the 28th day,the body mass was still lower than that of the sham-operation group(P<0.05);on the first day after operation,the mNSS score significantly increased,gradually decreased thereafter,and remained higher than the sham-operation group until the 28th day(P<0.01);the percentage of stiff immobility time significantly decreased on the first day after operation,gradually stabilized,and remained lower than the sham-operation group on the 28th day(P<0.05);the hippocampal tissue structure was significantly damaged,and the density of Ki67+DCX+NeuroD1 positive cells in the dentate gyrus of hippocampus was significantly increased(P<0.05),the expression of SV2A protein in the dentate gyrus of hippocampal was significantly decreased(P<0.05).Compared with the model group,the body mass of rats in the electroacupuncture group showed an increasing trend(P<0.05),the mNSS score decreased(P<0.01),and the percentage of stiff immobility time increased(P<0.05);the ischemic injury area was significantly reduced,the structure was clearer,and the disordered and irregularly cells arrangement were reduced,the density of Ki67+DCX+NeuroD1 positive cells in the dentate gyrus of hippocampus significantly increased(P<0.05),and the expression of SV2A protein in the dentate gyrus of hippocampal significantly increased(P<0.05).Conclusion Electroacupuncture at acute phase at"Baihui"and"Shenting"can promote the recovery of cognitive dysfunction in MCAO rats in the later stage,and its mechanism may be related to enhancing the proliferation and differentiation of neural precursor cells in the dentate gyrus of hippocampus,promoting neurogenesis.

Objective To explore the effects and potential mechanism of electroacupuncture at acute phase on cognitive dysfunction at later stage in rats with middle cerebral artery occlusion(MCAO).Methods Totally 39 SD rats were randomly divided into sham-operation group,model group and electroacupuncture group,with 13 rats in each group.MCAO model was established by Zea Longa thread embolism method in model group and electroacupuncture group.The sham-operation group only separated blood vessels.Electroacupuncture group was treated with electroacupuncture at"Baihui"and"Shenting"acupoints at 5 min and 6 h after model establishment respectively,for 30 min.The body mass,modified neuropathy severity scale(mNSS),and percentage of stiff immobility time of rats were monitored weekly,Nissl staining was used to observe the morphology of hippocampal tissue on the 28 d,immunofluorescence staining was used to detect the expression of Ki67,dual cortin(DCX)and neuronal differentiation factor 1(NeuroD1)in dentate gyrus of the hippocampus,the expression of synaptic vesicle protein 2A(SV2A)protein in dentate gyrus of hippocampus was detected by Western blot.Results Compared with the sham-operation group,on the first day after operation,the body mass of the model group rats decreased,then gradually increased,and on the 28th day,the body mass was still lower than that of the sham-operation group(P<0.05);on the first day after operation,the mNSS score significantly increased,gradually decreased thereafter,and remained higher than the sham-operation group until the 28th day(P<0.01);the percentage of stiff immobility time significantly decreased on the first day after operation,gradually stabilized,and remained lower than the sham-operation group on the 28th day(P<0.05);the hippocampal tissue structure was significantly damaged,and the density of Ki67+DCX+NeuroD1 positive cells in the dentate gyrus of hippocampus was significantly increased(P<0.05),the expression of SV2A protein in the dentate gyrus of hippocampal was significantly decreased(P<0.05).Compared with the model group,the body mass of rats in the electroacupuncture group showed an increasing trend(P<0.05),the mNSS score decreased(P<0.01),and the percentage of stiff immobility time increased(P<0.05);the ischemic injury area was significantly reduced,the structure was clearer,and the disordered and irregularly cells arrangement were reduced,the density of Ki67+DCX+NeuroD1 positive cells in the dentate gyrus of hippocampus significantly increased(P<0.05),and the expression of SV2A protein in the dentate gyrus of hippocampal significantly increased(P<0.05).Conclusion Electroacupuncture at acute phase at"Baihui"and"Shenting"can promote the recovery of cognitive dysfunction in MCAO rats in the later stage,and its mechanism may be related to enhancing the proliferation and differentiation of neural precursor cells in the dentate gyrus of hippocampus,promoting neurogenesis.