Effects of electroacupuncture on the integrity of myelin and the expressions of myelin-related proteins in the spinal dorsal horn of neuropathic pain model rat
Objective To investigate the effect of electroacupuncture treatment on the integrity of myelin and the related molecules in the spinal dorsal horn of neuropathic pain model rat.Methods Totally 32 SPF grade Sprague-Dawley rats were randomly divided into 4 groups:sham group,pain model group,electroacupuncture group and sham electroacupuncture group,with 8 rats in each group.Neuropathic pain model was established by right sciatic nerve ligation.Electroacupuncture stimulation of Huantiao point and Yanglingquan point was started from 1 day after surgery,30 min/d,and lasted for 14 days.The paw withdraw mechanical threshold(PWMT)were tested before surgery,3 days,7 days and 14 days after surgery.Immu-nofluorescence was used to detect myelin basic protein(MBP)in the ipsilateral Ⅰ-Ⅲ laminae of spinal dor-sal horn and Western blot was used to measure the expression of β-secreatase 1(BACE1),neuregulin 1 typeⅢ(NRG1 Ⅲ)and phosphorylated ErbB receptor tyrosine kinase 2(p-ErbB2)at 14 days after surgery.SPSS 24.0 was used for statistical analysis.Repeated measurement ANOVA was used for behavioral analysis and one-way ANOVA followed by Bonferroni test was used for Western blot and immunofluorescence data a-nalysis.Results(1)The results of pain behaviors showed that the interaction effect of time and group on PWMT was significant(F=29.817,P＜0.001),and both the time main effect(F=240.598,P＜0.001)and group main effect(F=304.291,P＜0.001)were significant.There were no significant differences among 4 groups before surgery.Compared with pain model group,the PWMT of electroacupuncture group were signifi-cantly increased at 3 days((16.87±1.82)g,(11.31±1.36)g),7 days((15.09±1.75)g,(10.33±0.73)g)and 14 days((15.07±1.49)g,(9.87±0.98)g)after surgery(all P＜0.01).(2)The differ-ence of the intensity of MBP in the ipsilateral Ⅰ-Ⅲ laminae of spinal dorsal horn staining was significant a-mong 4 groups(F=92.06,P＜0.001).Compared with sham group,the intensity of MBP staining in the ipsi-lateral Ⅰ-Ⅲ laminae of spinal dorsal horn in pain model group was significantly decreased((13.26±1.90)％,(36.37±0.68)％)(P＜0.01)).Compared with pain model group,the intensity of MBP staining in the ipsilateral Ⅰ-Ⅲ laminae of spinal dorsal horn in electroacupuncture group((28.21±3.15)％)was significantly increased after electroacupuncture treatment(P＜0.01).(3)The differences of the expressions of BACE1,NRG1 Ⅲ and p-ErbB2 in the ipsilateral Ⅰ-Ⅲ laminae of spinal dorsal horn were significant a-mong the 4 groups(F=31.04,21.20,11.74,all P＜0.01).Compared with sham group,the expressions of BACE1,NRG1 Ⅲ and p-ErbB2 in the ipsilateral Ⅰ-Ⅲ laminae of spinal dorsal horn in pain model group were significantly downregulated(BACE1(0.42±0.09),(1.16±0.13);NRG1 Ⅲ(0.54±0.05),(1.00±0.10);p-ErbB2(0.73±0.06),(1.02±0.15))(all P＜0.05).Compared with pain model group,the ex-pression of BACE1(0.86±0.09),NRG1 Ⅲ(0.81±0.05)and p-ErbB2(1.12±0.04)in the ipsilateralⅠ-Ⅲ laminae of spinal dorsal horn in electroacupuncture group were upregulated(all P＜0.05).Conclusion Electroacupuncture treatment could relieve neuropathic pain,improve the demyelination and upregulate the expressions of myelin-related proteins in the ipsilateral Ⅰ-Ⅲ laminae of spinal dorsal horn.
NETL
NSTL
万方数据
