TY - JOUR A1 - Wijnvoord, Nina A1 - Albuquerque, Boris A1 - Häussler, Annett A1 - Myrczek, Thekla A1 - Popp, Laura A1 - Tegeder, Irmgard T1 - Inter-strain differences of serotonergic inhibitory pain control in inbred mice T2 - Molecular pain N2 - Background: Descending inhibitory pain control contributes to the endogenous defense against chronic pain and involves noradrenergic and serotonergic systems. The clinical efficacy of antidepressants suggests that serotonin may be particularly relevant for neuropathic pain conditions. Serotonergic signaling is regulated by synthesis, metabolisms, reuptake and receptors. To address the complexity, we used inbred mouse strains, C57BL/6J, 129 Sv, DBA/2J and Balb/c, which differ in brain serotonin levels. Results: Serotonin analysis after nerve injury revealed inter-strain differences in the adaptation of descending serotonergic fibers. Upregulation of spinal cord and midbrain serotonin was apparent only in 129 Sv mice and was associated with attenuated nerve injury evoked hyperalgesia and allodynia in this strain. The increase of dorsal horn serotonin was blocked by hemisectioning of descending fibers but not by rhizotomy of primary afferents indicating a midbrain source. Para-chlorophenylalanine-mediated serotonin depletion in spinal cord and midbrain intensified pain hypersensitivity in the nerve injury model. In contrast, chronic inflammation of the hindpaw did not evoke equivalent changes in serotonin levels in the spinal cord and midbrain and nociceptive thresholds dropped in a parallel manner in all strains. Conclusion: The results suggest that chronic nerve injury evoked hypernociception may be contributed by genetic differences of descending serotonergic inhibitory control. Y1 - 2010 UR - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/20397 UR - https://nbn-resolving.org/urn:nbn:de:hebis:30-84053 N1 - © 2010 Wijnvoord et al., licensee BioMed Central Ltd. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. VL - 6 IS - Art. 70 SP - 1 EP - 11 PB - Sage CY - London ER -