Skip to main content

(NAS Colloquium) The Neurobiology of Pain (1999) / Chapter Skim
Currently Skimming:

The Spinal Biology in Humans and Animals of Pain States Generated by Persistent Small Afferent Input
Pages 7680-7686

The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.


From page 7680...
... nR1~. once tOPn~rtment of Ane~theci`,l`~ov Whim University School of Medicine, 1-8-1 Inohana Chno-ku Chiba-shi, 260 Japan ABSTRACT Behavioral models indicate that persistent small afferent input, as generated by tissue injury, results in a hyperalgesia at the site of injury and a tactile allodynia in areas adjacent to the injury site.
Read the entire page →
From page 7681...
... Role of Spinal and Peripheral Systems in the Post-Tissue Injury Pain State The behavioral sequelae outlined above, showing a hyperalgesic/allodynic state after tissue injury, may result from a peripheral sensitization secondary to the injury and/or to a change in central processing initiated by the persistent small afferent input generated by the injury. Blockade of spinal activation by the spinal delivery of a local anesthetic (11)
Read the entire page →
From page 7682...
... The overview of connectivity suggests elements that define a portion of the organization of spinal systems that encode activity generated by small afferent input. The contribution of these several spinal systems in nociceptive processing can be determined by considering the effects of systematically altering spinal pharmacology on pain behavior generated by acute high intensity and tissue injurious stimuli.
Read the entire page →
From page 7683...
... and the second phase of the formalin test (47, 48~. System Interactions As reviewed above, after local injury, the behaviorally defined components of post-tissue injury pain states reflect an increased receptive field and a left shift in the stimulus response curve for spinal dorsal horn neurons, which is evoked initially and then sustained in part by persistent small afferent input.
Read the entire page →
From page 7684...
... Thus, repetitive afferent input increases excitatory amino acid and peptide release from primary afferents that serve to initially depolarize dorsal horn neurons. Persistent depolarization serves to increase intracellular calcium, activating a variety of intracellular enzymes (COX-2 and NOS)
Read the entire page →
From page 7685...
... The evidence presented here clearly reflects the functional complexity of the events that occur secondary to a focal injury, leading to a persistent small afferent barrage. The fact that such stimuli will lead to a local 1° hyperalgesia and 2° tactile allodynia raises the likelihood that specific components of the post-tissue injury pain state may have distinct components.
Read the entire page →
From page 7686...
... 7686 Colloquium Paper: Yaksh et al. Chaplan, S
Read the entire page →

Key Terms

  • afferent input
  • pain states
  • tissue injury
  • nmda receptor
  • tactile allodynia

  • spinal delivery
  • pain behavior
  • formalin test
  • human pain
  • thermal escape

  • primary afferent
  • nociceptive processing
  • amino acids
  • spinal pharmacology
  • afferent barrage

  • transmitter release
  • acute nociceptive
  • horn neurons
  • pain state
  • hot plate

  • wdr neurons
  • thermal hyperalgesia
  • spinal nmda
  • injury pain
  • intrathecal nmda

  • spinal cord
  • receptor antagonists
  • receptor agonists
  • hyperalgesia induced
  • injury site


    • This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
    More information on Chapter Skim is available.