Major contribution of Aδ-fibres to increased reflex transmission in the feline spinal cord during acute muscle inflammation
Major contribution of Aδ-fibres to increased reflex transmission in the feline spinal cord during acute muscle inflammation
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DOI：
10.1016/j.neures.2011.10.006
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发表时间：
2012-02-01
影响因子：
2.9
通讯作者：
Sears, Thomas A.
中科院分区：
文献类型：
--
作者：
Schomburg, Eike D.;Steffens, Heinz;Sears, Thomas A.
激活的伤害性肌肉传入神经对病理性肌张力增加的贡献仍然不清楚。本研究的目的是调查是否急性肌炎的腓肠肌比目鱼肌（GS）的影响脊髓反射活动，并测试是否A δ纤维或C纤维主要负责任何影响。在高脊髓猫单突触反射（MR）的屈肌和伸肌和传输的反射通路从第III和IV组肌肉传入（激活动脉内注射氯化钾）进行了研究。GS与角叉菜胶浸润后，屈肌和伸肌的MR明显增加，再加上屈肌的便利化，由化学活化的III组和IV组传入诱导。这些传入引起的伸肌抑制也主要是增强，但不太一致。角叉菜胶的反射作用在1h内开始，约1.5h后达到最大。在通过TTX阻断所有有髓鞘A纤维（包括A δ纤维）从发炎肌肉的输入后，仅对MR保持小的易化作用，并且在到屈肌PBSt的兴奋性通路中的兴奋性传递的易化被废除。结果表明角叉菜胶引起的炎症反应对脊髓反射功能的影响主要来自A δ纤维。(C)2011 Elsevier爱尔兰有限公司和日本神经科学学会。All rights reserved.
The contribution of activated nociceptive muscle afferents to pathologically increased muscle tone remains obscure. The aim of the present study was to investigate whether an acute myositis of the gastrocnemius-soleus (GS) influences spinal reflex activity and to test whether A delta-fibre or C-fibre were mainly responsible for any effects. In high spinal cats monosynaptic reflexes (MRs) of flexors and extensors and transmission in reflex pathways from group III and IV muscle afferents (activated by intra-arterial KCI injection) were investigated. After infiltration of GS with carrageenan there was a distinct increase in the MRs of flexors and extensors, coupled with facilitation of the flexors, induced by chemically activated group III and IV afferents. The inhibition evoked in extensors by these afferents was also mainly enhanced but less consistently. The reflex effects of carrageenan started within 1 h and reached their maximum after about 1.5 h. After blocking the input of all myelinated A-fibres, including A delta-fibres, from the inflamed muscle by TTX, only a small facilitatory effect on MRs remained and the facilitation of excitatory transmission in the excitatory pathway to the flexor PBSt was abolished. The results show that the action of carrageenan-induced inflammation on spinal reflex function derives mainly from A delta-fibres. (C) 2011 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.