RESUMEN
Objective:To investigate the effect and the mechanism of electroacupuncture(EA)on corpus striatum white matter injury in rats with focal cerebral ischemia(FCI).Methods:Forty-four specific-pathogen-free Sprague-Dawley rats were divided into a normal group(n=10),a sham-operation group(sham group,n=10),and a modeling group(n=24)using the random number table method.The normal group was a blank control.In the sham group,only the vessels and vagus nerve were isolated without embolization.The FCI rat model in the modeling group was replicated using the middle cerebral artery occlusion embolization method.The 20 successfully modeled rats were randomly divided into a model group and an EA group,with 10 rats in each group.Rats in the model group did not receive further treatment.Rats in the EA group received EA stimulation at Baihui(GV20)and the left Zusanli(ST36)24 h after the successful modeling,30 min each time,once a day for 14 d.On the 14th day of the experiment,rats in each group were scored for neurological deficits and then sacrificed,and brain tissues containing corpus striatum around the ischemic focus were paraffin-embedded from 5 rats in each group.Luxol fast blue(LFB)staining was used to detect damage changes in the white matter.The positive immunoreactive expression of myelin basic protein(MBP),myelin-associated growth inhibitor A(Nogo-A)and its receptor(NgR)in rat corpus striatum tissue was detected by immunohistochemistry staining,and then the protein expression of MBP,Nogo-A,and NgR in the corpus striatum tissue around the ischemic focus was determined by Western blotting.Results:Compared with the normal group and the sham group,the model group had a significantly higher neurological deficit score(P＜0.05)and fiber bundle injuries in the corpus striatum white matter,evidenced by a significantly lower mean optical density value of corpus striatum LFB staining(P＜0.05),a significantly lower MBP expression level(P＜0.05),and significantly higher Nogo-A and NgR protein expression levels(P＜0.05).Compared with the model group,the neurological deficit score was significantly lower(P＜0.05),the mean optical density value of LFB staining was significantly higher(P＜0.05),the MBP expression level was increased(P＜0.05),and the expression levels of Nogo-A and NgR proteins were decreased(P＜0.05)in the EA group.Conclusion:EA reduces the ischemia-induced corpus striatum white matter injury and improves neurological deficits.The mechanism may be related to the inhibition of Nogo-A/NgR activation.