神经源性痛大鼠模型腰髓后角A_β纤维生芽的变化(英文)

CHANGES OF A_β FIBERS SPROUTING IN DORSAL HORN OF LUMBAR CORD ON NEUROPATHIC PAIN MODEL IN RATS

已有研究表明 ,外周神经损伤后 Aβ神经元的初级传入末梢在脊髓的病理性生芽与损伤后痛觉超敏的形成有关。为了证实外周神经损伤后形成的这种生芽是否具有可逆性 ,本研究以大鼠坐骨神经压迫造成神经源性痛模型 ,采用跨神经节的霍乱毒素 B亚单位结合辣根过氧化物酶 ( CB-HRP)作为示踪剂 ,四甲基联苯胺 ( TMB)反应呈色追踪 Aβ初级传入末梢。结果证实 :对坐骨神经的压迫也能够导致痛觉过敏和 Aβ纤维末梢生芽侵入脊髓后角 层 ,并且这种生芽不伴随对神经压迫的解除而逆转。

It is proposed that following peripheral nerve injury abnormal sprouting of A β fiber primary afferent neurons in the spinal cord contributes to the allodynia that often occurs with such injury. The present investigation is to determine whether this sprouting is reversal after compression of peripheral nerve was relieved. In a rat model of neuropathic pain made by rat sciatic nerve compression,chorela toxin B subunit conjugated horseradish peroxidase (CB-HRP) was used to trace the termination of A-fiber primary afferents and sections were reacted for using tetramethylbenzidine (TMB) as the chromagen. We demonstrated that the compression to the sciatic nerve also results in hyperalgesia and novel transganglionic CB-HRP staining in laminae II, and this sprouting can not be reversed by decompression. This structural reorganization in central nervous system and its irreversible character may contribute to the development and maintenance of neuropathic pain.