Differences in the Effect of TENS Frequencies on Pain Behavior,Myelin Regeneration,and Functional Recovery in Rats with Neuropathic Pain

LU Sheng-you; CHEN Mei-qin; JIANG Rui-fang; LU Yi; LIAO Wan-heng

摘要：Objective:To observe the differences in pain behavioral indicators,myelin regeneration,and neurological functional recovery in neuropathic pain(NP)rats treated with transcutaneous electrical nerve stimulation(TENS)at different frequencies.Methods:A total of 25 adult SD rats were randomly divided into a control group,model group,low-frequency group,medium-frequency group,and high-frequency group,with 5 rats in each group.The control group underwent a sham surgery with L5 spinal nerve ligation only,while the other groups were subjected to the L5 spinal nerve ligation and transection method to establish NP rat models.The low-frequency group received 20 Hz TENS therapy,the medium-frequency group received 75 Hz TENS therapy,and the high-frequency group received 100 Hz TENS therapy,once daily for 14 d.Spontaneous pain behavior scores,modified neurological severity scores(mNSS),and morphological changes in nerve myelin were recorded for all groups.Results:NP animal models were successfully established.Compared with the control group,the model group exhibited significantly higher spontaneous pain behavior scores,mNSS scores,and myelin basic protein(MBP)levels at all observation time points.The low-frequency group showed improvement in all indicators at 7 d,but mNSS scores and MBP levels increased again at 14 d.The medium-frequency group demonstrated continuous declines in mNSS scores post-treatment,with significant improvement compared to the model group,and lower mNSS scores and MBP levels than both the low-frequency and model groups at 14 d.The high-frequency group showed sustained decreases in mNSS scores at 7 and 14 d,reaching the lowest scores at 14 d,with the most significant improvement in all indicators compared to the model group,exhibiting statistical significance(P<0.05).Conclusion:TENS interventions at different frequencies improved neuropathic pain behaviors and neurological recovery in NP rat models.However,100 Hz TENS therapy promoted faster myelin regeneration and exerted more positive effects on reducing abnormal pain behaviors and repairing neural damage.