Long-Term Potentiation in Superficial Spinal Dorsal Horn: A Pain Amplifier

  • Ruth Drdla
  • Jürgen Sandkühler


Long-term potentiation of synaptic strength (LTP) is one of the most intensively studied models of lasting signal amplification in the nervous systems. LTP has also been identified at synapses between small primary afferent Aδ- or C-fibres, many of which are nociceptive, and 2nd order neurons in superficial spinal dorsal horn. In the present chapter we review fundamental properties of spinal LTP and we describe different induction protocols including electrical nerve stimulation, acute nerve injury and noxious stimulation such as capsaicin or formalin intraplantar injections. The presently known signal transduction pathways leading to LTP in pain pathways include activation of NMDA receptor and NK1 receptors for substance P, opening of T-type voltage-gated calcium channel, release of Ca2+ from intracellular stores, as well as activation of PKC and CaMKII. These signalling pathways are similar to those leading to hyperalgesia. The converging and independent evidence summarized in this chapter suggests that LTP at the first synapse in pain pathways may underlie various forms of hyperalgesia following trauma, inflammation or nerve injury.


Conditioning Stimulus Chronic Constriction Injury Synaptic Strength Spare Nerve Injury High Frequency Stimulation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



Ca2+ calmodulin dependent kinase II


cAMP-response element binding protein


gamma-aminobutyric acid


glutamate transporter 1




International Association for the Study of Pain




inositol triphosphate


long-term depression


long-term potentiation


mitogen activated kinase


metabotropic glutamate receptor


not tried


neurokinin 1 receptor






nitric oxide


protein kinase A


protein kinase C


phospholipase C




voltage-dependent Ca2+ channel


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Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  1. 1.Department of NeurophysiologyCenter for Brain Research, Medical University of ViennaAustria

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