脊神经节损伤介导的脊髓背角EAAs和IAAs变化的实验研究

目的：研究脊神经节（ＤＲＧ）炎性损伤时，脊髓背角兴奋性氨基酸（ＥＡＡｓ）、抑制性氨基酸（ＩＡＡｓ）含量和脊髓背角谷氨酸（Ｇｌｕ）、天门冬氨酸（Ａｓｐ）免疫组织化学的变化，及其与实验动物神经行为异常变化之间的关系。方法：健康家兔５４只，随机分为手术对照组（ｎ＝２４）；炎症损伤组（ｎ＝２４）和正常对照组（ｎ＝６）。采用组织氨基酸的含量分析仪测定脊髓背角Ｇｌｕ、Ａｓｐ、γ氨基丁酸（ＧＡＢＡ）、牛磺酸（Ｔａｕ）、苏氨酸（Ｔｈｒ）和色氨酸（Ｓｅｒ）含量，采用免疫组化法观察脊髓背角Ｇｌｕ和Ａｓｐ分布特点及变化。结果：ＤＲＧ炎症损伤介导脊髓背角ＥＡＡｓ和ＩＡＡｓ释放增加。结论：ＥＡＡｓ在痛觉过敏的形成和维持中具有重要作用，而ＩＡＡｓ的增加则与机体抗伤害性保护反应相关。ＤＲＧ炎症损伤初期，脊髓背角ＥＡＡｓ／ＩＡＡｓ动态平衡的破坏是伤害性神经细胞兴奋性损伤和伤侧肢体痛觉过敏的主要原因。

The experimental study of the EAAs and IAAs contents changes in the dorsal horn of spinal cord induced by DRG injury

Objective:To study the alternations of excitatory amino acids(EAAs),inhibitory amino acids(IAAs) contents and the distribution properties of Glu,Asp immunoreactivity in the dorsal horn of spinal cord.In addition,the relations between the abnormal neuro behavior and the changes induced by inflammatory reaction of DRG would be investigated.Method:Fifty four health rabbits were divided into three groups:sham operative(n=24),inflammatory injury(n=24) and control group(n=6).The tissue content of EAAs(Glu,Asp),IAAs(GABA,Tau) and neutral amino acids(Ser,Thr) were determined in the dorsal horn of spinal cord (SDH).The distribution features of Glu and Asp were also studied by immunohistochemical analyse.Result:The EAAs and IAAs increased greatly induced by DRG inflammatory injury.Conclusion:The increase of EAAs release in SDH induced by inflammatory irritation played an important role in promoting and maintaining hyperalgesia, but increase of IAAs release is mainly related to protective mechanism. The balance of EAAs/IAAs destroyed by inflammatory injury of DRG was a main factor of the hyperexcitotoxicity injury of nociceptive neurons and hyperalgesia development.