BDNF and TrkB Mediated Mechanisms in the Spinal Cord

  • Rita Bardoni
  • Adalberto Merighi


The neurotrophin brain-derived neurotrophic factor (BDNF) plays an essential role during development, promoting the survival of specific populations of central and peripheral neurons. During adulthood, BDNF also acts as a synaptic modulator in several areas of the central nervous system (CNS), including the spinal cord, and is involved in short and long term changes of synaptic efficacy. In spinal cord dorsal horn BDNF is expressed in the peptidergic terminals originating from primary afferent fibres, while its high affinity receptor trkB has been detected on both primary afferent terminals and dorsal horn neurons. In superficial dorsal horn, exogenous BDNF modulates fast excitatory (glutamatergic) and inhibitory (GABAergic/glycinergic) signals, as well as slow peptidergic neurotransmission. Conditions of inflammatory and neuropathic pain alter the expression of BDNF and trkB receptors in dorsal horn. In experimental pain models, modulation of synaptic transmission by BDNF plays an important role in the induction and maintenance of central sensitization.


Nerve Growth Factor Dorsal Horn Peripheral Nerve Injury Chronic Constriction Injury Intrathecal Administration 
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.



α-amino-methyl-isoxazole-propionic acid


brain derived neurotrophic factor


chronic constriction injury


complete Freund’s adjuvant


calcitonin gene-related peptide


central nervous system


cyclic AMP response element binding protein


dense core vesicle


dorsal root ganglion


excitatory post-synaptic currents


extracellular signal-regulated kinase


full-length trkB receptor


γ-amino butyric acid


potassium-chloride co-transporter 2


mitogen-activated protein kinase


MAPK/ERK kinase


nerve growth factor






common neurotrophin low affinity receptor


primary afferent fibre


protein kinase C


phospholipase C


peripheral nervous system


post-synaptic density


spinothalamic tract


tumour necrosis factor α


tropomyosine receptor kinase A


tropomyosine receptor kinase B


tropomyosine receptor kinase C


truncated trkB receptor



The work described in this paper has been funded by the Italian Ministry of Education and Scientific Research (Fondi PRIN), Compagnia di San Paolo, Torino, and Fondazione CRT, Torino. We are greatly indebted to Dr. Chiara Salio for her kind gift of unpublished electron micrographs, and to Mr. Gianfranco Zanutto for his excellent graphic artwork.


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Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  1. 1.Department of Biomedical SciencesUniversity of Modena and Reggio EmiliaModenaItaly
  2. 2.Department of Veterinary MorphophysiologyUniversity of Turin, Istituto Nazionale di NeuroscienzeItaly

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