Elsevier

Neuroscience Letters

Volume 384, Issues 1–2, 12–19 August 2005, Pages 162-167
Neuroscience Letters

Long-lasting recovery of locomotor function in chronic spinal rat following chronic combined pharmacological stimulation of serotonergic receptors with 8-OHDPAT and quipazine

https://doi.org/10.1016/j.neulet.2005.04.062Get rights and content

Abstract

In chronic spinal rats, long-term stimulation of 5-HT receptors with quipazine or 8-OHDPAT by means of daily injection, promotes robust locomotor recovery. The question of a possible potentiation between treatments when applied together was addressed. Daily injections of both 8-OHDPAT and quipazine, were performed for a month in spinal animals. Animals were placed on a treadmill and the bipedal hindlimb locomotion was tested. Motor performances (behavioural test) and locomotor parameters (EMG and kinematic) were analysed weekly during the treatment. Furthermore, the locomotor performances were evaluated during two supplemental months following the end of the treatment. Our results suggest that association of both agonists induced long-lasting positive effects on locomotor function. Motor performances were significantly better after combined injection of both drugs than when the agonists were used separately. But, the most significant and new result is that the locomotor scores did not decrease during the weeks that followed the end of the treatment. These results suggests a long-lasting and 5-HT-dependent reorganisation of spinal networks.

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Acknowledgments

This work was funded by grants from the Christopher Reeve Paralysis Foundation (CRPF) and from the Institut de Recherche sur la Moelle et l’Encéphale (IRME). The authors warmly thank P. Drapeau and Pr. S. Rossignol at the CRSN, University of Montréal (Québec) for providing their homemade and powerful, software Expresso. We are grateful to K. Todd for his valuable comments. Myriam Antri received a fellowship from IRME.

References (32)

  • M. Antri et al.

    Locomotor recovery in the chronic spinal rat: effects of long-term treatment with a 5-HT2 agonist

    Eur. J. Neurosci.

    (2002)
  • A. Björklund et al.

    Neural transplantation in adult rats

  • J.R. Cazalets et al.

    Activation of the central pattern generators for locomotion by serotonin and excitatory amino acids in neonatal rat

    J. Physiol.

    (1992)
  • V. Cornea-Hebert et al.

    Cellular and subcellular distribution of the serotonin 5-HT2A receptor in the central nervous system of adult rat

    J. Comp. Neurol.

    (1999)
  • S. Doly et al.

    5-HT5A receptor localization in the rat spinal cord suggests a role in nociception and control of pelvic floor musculature

    J. Comp. Neurol.

    (2004)
  • S. Doly et al.

    The 5-HT2A receptor is widely distributed in the rat spinal cord and mainly localized at the plasma membrane of postsynaptic neurons

    J. Comp. Neurol.

    (2004)
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