Nagy I, Miller B A, Woolf C J
Department of Anatomy and Developmental Biology, University College London, UK.
Neuroreport. 1994 Oct 27;5(16):2105-8. doi: 10.1097/00001756-199410270-00029.
Small diameter primary afferents produce slow synaptic potentials in spinal neurones. These can be recorded as prolonged ventral root potentials (VRPs) in the isolated neonatal rat spinal cord preparation. The VRP elicited by stimulating C-fibres consists of two phases: an early phase comprising a monosynaptic and a short polysynaptic response identical to that elicited by low threshold A beta fibres and a late phase which has an initial component (0.1-1 s) which is sensitive to N-methyl-D-aspartic acid receptor antagonism and a very long lasting second component (1-20 s) which is resistant to these antagonists. We now demonstrate that the slowest component of the VRP is significantly reduced by both NK1 and NK2 tachykinin receptor antagonists and as a consequence, tachykinins have a particular contribution to the cumulative depolarization produced by low frequency (1 Hz) C-fibre stimulation.
小直径初级传入纤维在脊髓神经元中产生缓慢的突触电位。在离体新生大鼠脊髓标本中，这些电位可记录为延长的腹根电位（VRP）。刺激C纤维引发的VRP包括两个阶段：早期阶段包括一个单突触和一个短的多突触反应，与低阈值Aβ纤维引发的反应相同；晚期阶段有一个初始成分（0.1 - 1秒），对N - 甲基 - D - 天冬氨酸受体拮抗作用敏感，还有一个非常持久的第二成分（1 - 20秒），对这些拮抗剂有抗性。我们现在证明，NK1和NK2速激肽受体拮抗剂均可显著降低VRP的最慢成分，因此，速激肽对低频（1赫兹）C纤维刺激产生的累积去极化有特殊作用。
