Clinical Short Communication| Volume 378, P59-62, July 15, 2017

Improved strength on 5-hydroxytryptophan and carbidopa in spinal cord atrophy

  • Gabriella A. Horvath
    Corresponding author at: University of British Columbia, BC Children's Hospital, 4480 Oak St., Vancouver, BC V6H 3V4, Canada.
    BC Children's Hospital, Division of Biochemical Diseases, Department of Pediatrics, University of British Columbia, 4480 Oak St., Vancouver, BC V6H 3V4, Canada

    Vancouver General Hospital, Adult Metabolic Diseases Clinic, 2775 Laurel St., Vancouver, BC V5Z 1M9, Canada
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  • Lorelyn Meisner
    BC Children's Hospital, Department of Physiotherapy, 4480 Oak St., Vancouver V6H 3V4, Canada
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  • Kathryn Selby
    BC Children's Hospital, Division of Pediatric Neurology, Department of Pediatrics, University of British Columbia, 4480 Oak St., Vancouver V6H 3V4, Canada
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  • Robert Stowe
    Neuropsychiatry Program, Department of Psychiatry, University of British Columbia, UBC Hospital, 2255 Wesbrook Mall, Vancouver, BC V6T 2A1, Canada

    Neuropsychiatry Program, Department of Neurology, University of British Columbia, UBC Hospital, 2255 Wesbrook Mall, Vancouver, BC V6T 2A1, Canada
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  • Bruce Carleton
    BC Children's Hospital, Division of Translational Therapeutics, 4480 Oak St., Vancouver V6H 3V4, Canada
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Published:April 27, 2017DOI:


      • Lower limb spasticity, weakness, spinal cord atrophy, systemic serotonin deficiency
      • Biological effects of serotonin in developmental and adult neurogenesis in the CNS
      • Serotonergic enhancement can benefit motor function in severe spinal cord atrophy.


      There is ample evidence of an important role of descending serotonergic projections in modulating spinal motor neuron activation and firing, and experimental studies suggest that 5-HT receptor stimulation can improve motor function after spinal cord injury; however, relevant clinical data is sorely lacking. We describe two sisters with hemiplegic migraine, low CSF and platelet serotonin levels, and progressive spastic paraparesis associated with profound spinal cord atrophy whose lower extremity strength and ambulation responded to a precursor replacement strategy (5-hydroxytryptophan and carbidopa administration), an approach that may have broader applicability in myelopathies of diverse etiology where descending serotonergic projections are compromised.


      5HTP (5-hydroxytryptophan), 5HIAA (5-hydroxyindoleacidic acid), LAAD (l-amino acid decarboxylase), 5HT (serotonin (5-hydroxytryptamine))


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