Gao Lei, Zhang Jian-Feng, Williams John P, Yan Yi-Ning, Xiao Xi-Lai, Shi Wan-Rui, Qian Xiao-Yan, An Jian-Xiong
Department of Anesthesiology, Pain and Sleep Medicine, Aviation General Hospital of China Medical University and Beijing Institute of Translational Medicine, Chinese Academy of Sciences, Beijing, People's Republic of China.
School of Anesthesiology, Weifang Medical University, Weifang, Shangdong, People's Republic of China.
J Pain Res. 2021 Sep 14;14:2893-2905. doi: 10.2147/JPR.S322964. eCollection 2021.
It is unclear whether neuropathological structural changes in the peripheral nervous system and central nervous system can occur in the spared nerve injury model. In this study, we investigated the pathological changes in the nervous system in a model of neuropathic pain as well as the effects of electroacupuncture (EA) and pregabalin (PGB) administration as regards pain relief and tissue repair.
Forty adult male SD rats were equally and randomly divided into 4 groups: spared nerve injury group (SNI, n = 10), SNI with electroacupuncture group (EA, n = 10), SNI with pregabalin group (PGB, n =10) and sham-operated group (Sham, n=10). EA and PGB were given from postoperative day (POD) 14 to 36. EA (2 Hz and 100 Hz alternating frequencies, intensities ranging from 1-1.5-2 mA) was applied to the left "zusanli" (ST36) and "Yanglingquan" (GB34) acupoints for 30 minutes. The mechanical withdrawal thresholds (MWTs) were tested with von Frey filaments. Moreover, the organizational and structural alterations of the bilateral prefrontal cortex, hippocampus, sciatic nerves and the thoracic, lumbar spinal cords and dorsal root ganglions (DRGs) were examined via light and electron microscopy.
MWTs of left hind paw demonstrated a remarkable decrease in the SNI model (P < 0.05). In the SNI model, ultrastructural changes including demyelination and damaged neurons were observed at all levels of the peripheral nervous system (PNS) and central nervous system (CNS). In addition, EA improved MWTs and restored the normal structure of neurons. However, the effect was not found in the PGB treatment group.
Chronic pain can induce extensive damage to the central and peripheral nervous systems. Meanwhile, EA and PGB can both alleviate chronic pain syndromes in rats, but EA also restores the normal cellular structures, while PGB is associated with no improvement.
在 spared nerve injury 模型中，外周神经系统和中枢神经系统的神经病理结构变化是否会发生尚不清楚。在本研究中，我们调查了神经性疼痛模型中神经系统的病理变化，以及电针（EA）和普瑞巴林（PGB）给药对缓解疼痛和组织修复的影响。
40 只成年雄性 SD 大鼠平均随机分为 4 组： spared nerve injury 组（SNI，n = 10）、电针联合 spared nerve injury 组（EA，n = 10）、普瑞巴林联合 spared nerve injury 组（PGB，n = 10）和假手术组（Sham，n = 10）。从术后第 14 天至 36 天给予 EA 和 PGB。将 EA（2Hz 和 100Hz 交替频率，强度范围为 1 - 1.5 - 2mA）施加于左侧“足三里”（ST36）和“阳陵泉”（GB34）穴位 30 分钟。用 von Frey 细丝测试机械性撤针阈值（MWTs）。此外，通过光镜和电镜检查双侧前额叶皮质、海马、坐骨神经以及胸、腰脊髓和背根神经节（DRGs）的组织和结构改变。
SNI 模型中左后爪的 MWTs 显著降低（P < 0.05）。在 SNI 模型中，在外周神经系统（PNS）和中枢神经系统（CNS）的所有水平均观察到包括脱髓鞘和神经元损伤在内的超微结构变化。此外，EA 改善了 MWTs 并恢复了神经元的正常结构。然而，在 PGB 治疗组未发现此效果。
慢性疼痛可导致中枢和外周神经系统广泛损伤。同时，EA 和 PGB 均可减轻大鼠的慢性疼痛综合征，但 EA 还能恢复正常细胞结构，而 PGB 则无改善作用。
