Get access

Neurochemical and Immunocytochemical Studies on the Distribution of N-Acetyl-Aspartylglutamate and N-Acetyl-Aspartate in Rat Spinal Cord and Some Peripheral Nervous Tissues

Authors

  • L. Ory-Lavollée,

    1. Division of Child Psychiatry, Departments of Psychiatry, Neuroscience, Pharmacology, and Pediatrics, The Johns Hopkins University School of Medicine, Baltimore, Maryland, U.S.A.
    Search for more papers by this author
  • R. D. Blakely,

    1. Division of Child Psychiatry, Departments of Psychiatry, Neuroscience, Pharmacology, and Pediatrics, The Johns Hopkins University School of Medicine, Baltimore, Maryland, U.S.A.
    Search for more papers by this author
  • J. T. Coyle

    Corresponding author
    1. Division of Child Psychiatry, Departments of Psychiatry, Neuroscience, Pharmacology, and Pediatrics, The Johns Hopkins University School of Medicine, Baltimore, Maryland, U.S.A.
      Address correspondence and reprint requests to Dr. J. T. Coyle at Division of Child Psychiatry, Meyer 4-163, The Johns Hopkins University School of Medicine, 600 North Wolfe Street, Baltimore, MD 21205, U.S.A.
    Search for more papers by this author

Address correspondence and reprint requests to Dr. J. T. Coyle at Division of Child Psychiatry, Meyer 4-163, The Johns Hopkins University School of Medicine, 600 North Wolfe Street, Baltimore, MD 21205, U.S.A.

Abstract

Abstract: HPLC analysis of rat spinal cord revealed a uniform distribution of N-acetyl-aspartate (NAA) across both longitudinal and dorsoventral axes. In contrast, ventral cord N-acetyl-aspartylglutamate (NAAG) levels were significantly higher than those measured in dorsal halves of cervical, thoracic, and lumbar segments. Immunocytochemical studies using an affinity-purified antiserum raised against NAAG-bovine serum albumin revealed an intense staining of motoneurons within rat spinal cord. Along with the considerable NAAG content in ventral roots, these results suggest that NAAG may be concentrated in motoneurons and play a role in motor pathways. NAAG was also present in other peripheral neural tissues, including dorsal roots, dorsal root ganglia, superior cervical ganglia, and sciatic nerve. It is interesting that NAA levels in peripheral nervous tissues were lower than those in CNS structures and that NAA levels in ventral roots and sciatic nerve were lower than NAAG levels. These findings further document a lack of correlation between NAAG and NAA levels in both central and peripheral nervous tissues. Taken together, these data demonstrate the presence of NAAG in nonglutamatergic neuronal systems and suggest a more complex role of NAAG in neuronal physiology than previously postulated.

Get access to the full text of this article

Ancillary