论文部分内容阅读
深部脑刺激是一种广泛用于治疗中枢神经及精神疾病的功能型手术疗法。深部脑刺激在临床应用于疼痛治疗起源于半个多世纪以前,能够有效治疗多种类型的顽固疼痛,然而其作用机制尚不清楚。为了进一步探索其神经机制,首先需要建立合适的深部脑刺激治疗疼痛的动物模型。本研究在大鼠的中脑导水管周围灰质腹外侧区(ventrolateral periaqueductal gray,vl PAG)或丘脑腹后外侧核(ventral posterior lateral nucleus,VPL)埋置刺激电极,研究深部脑刺激对正常大鼠急性痛、完全弗式佐剂(complete Freund’s adjuvant,CFA)注射引起的慢性炎症痛大鼠模型以及脊神经结扎(spinal nerve ligation,SNL)手术引起神经病理痛大鼠模型的镇痛效果。主要结果如下:(1)在正常大鼠中,单侧vl PAG刺激能够显著提高双侧足底的热辐射痛阈,即产生显著的双侧镇痛作用;(2)在CFA建立的慢性炎症痛模型中,对侧vl PAG刺激和VPL刺激都能够显著提高CFA侧足底的热辐射痛阈,即产生显著的镇痛作用;(3)在SNL手术引发的慢性神经源性痛模型中,对侧VPL刺激能够显著提高SNL侧足底的机械痛阈,而vl PAG刺激对SNL引发的触诱发痛没有影响。以上结果提示,PAG刺激对于急性痛以及慢性炎症痛有着较好的镇痛效果,而VPL刺激更适合慢性炎症痛和慢性神经病理痛的镇痛研究。
Deep brain stimulation is a type of functional surgery that is widely used to treat central nervous and mental disorders. Deep brain stimulation in clinical application of pain treatment originated more than half a century ago, can effectively treat many types of stubborn pain, but its mechanism of action is not yet clear. In order to further explore its neural mechanism, we first need to establish a suitable animal model of deep brain stimulation for the treatment of pain. In this study, the stimulation electrodes were implanted in the ventrolateral periaqueductal gray (vl PAG) or ventral posterior lateral nucleus (VPL) in the rat middle cerebral aqueduct to investigate the effects of deep brain stimulation on normal rats Acute pain, chronic inflammatory pain model induced by complete Freund’s adjuvant (CFA) injection and analgesic effect of neuropathic pain rat model caused by spinal nerve ligation (SNL) surgery. The main results are as follows: (1) In normal rats, unilateral vl-PAG stimulation can significantly increase the heat radiation pain threshold of bilateral plantar, that is, significant bilateral analgesic effect; (2) in CFA established chronic inflammation Pain model, contralateral vl PAG stimulation and VPL stimulation can significantly increase the thermal radiation pain threshold of the CFA side of the foot, that is, significant analgesic effect; (3) SNL surgery-induced chronic neuropathic pain model, Contralateral VPL stimulation significantly increased the mechanical pain threshold on the SNL side of the foot, whereas vl PAG stimulation had no effect on SNL-induced tactile allodynia. The above results suggest that PAG stimulation has a good analgesic effect on acute pain and chronic inflammatory pain while VPL stimulation is more suitable for analgesic research on chronic inflammatory pain and chronic neuropathic pain.