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Neurochemical Research

, Volume 18, Issue 7, pp 731–736 | Cite as

Effect of unilateral motor cortex ablation on activity of choline acetyltransferase and levels of amino acid transmitter candidates in the spinal cord of adult monkeys

  • Kimikazu Fujita
  • Yutaka Nagata
  • Kohichi Konno
  • Tetsuo Kanno
  • Kamaravelu Selvakumar
Original Articles

Abstract

Evidence thatl-glutamate is a neurotransmitter of corticofugal fibers was sought by measuring changes in several biochemical markers of neurotransmitter function in discrete regions of spinal cord after ablation of sensorimotor cortex in monkeys. One and five weeks after unilateral cortical ablation, samples from six areas of spinal cord (ventral, lateral and dorsal regions of the left and right sides) were analysed for choline acetyltransferase (ChAT) activity and contents of amino acid transmitter candidates-glutamic acid (Glu), aspartic acid (Asp), glycine (Gly), taurine (Tau) and γ-aminobutyric acid (GABA). During one to five weeks after unilateral cortical ablation of the monkey, prolonged hemiplegia in the contralateral side was observed. Histological examination of the spinal cord 5 weeks after unilateral (left) cortical ablation showed no apparent change in either control (ipsilateral, left) or affected (contralateral, right) sides of the cord as examined by the Klüver-Barrera method. The ChAT activity as a cholinergic marker was scarcely changed in any region of either left (control) or right (affected) side of the spinal cord at one and five weeks after unilateral (left side) ablation of the motor cortex. Amino acid levels in each region of the spinal cord were not significantly changed one week after unilateral ablation of the motor cortex. However, a significant decrease of Glu content was observed in the lateral column of the affected (right) side compared to the control (left) side of cervical and lumbar cord five weeks after cortical ablation of the left motor area. No concomitant alterations of other amino acids were detected. These data strongly suggest thatl-Glu is a neurotransmitter for corticofugal pyramidal tract fibers to anterior horn secondary neurons related to motor control activity in monkey spinal cord.

Key Words

Acetylcholine choline acetyltransferase aspartic acid glutamic acid 

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References

  1. 1.
    Brodal, A. 1981. Neurological Anatomy in Relation to Clinical Medicine. 3rd Ed., Oxford Univ. Press, New York.Google Scholar
  2. 2.
    Laurence, D.G. and Kuypers, H.G.S. 1968. The functional organization the motor system in the monkey. 2, The effects of lesions of the descending brain-stem pathways. Brain Res. 91:15–36.Google Scholar
  3. 3.
    Stone, T.W. 1973. Cortical pyramidal tract interneurones and their sensitivity tol-glutamic acid. J. Physiol. 223:211–225.Google Scholar
  4. 4.
    Stone, T.W. 1976. Blockade by amino acid antagonists of neuronal excitation mediated by the pyramidal tract. J. Physiol. 257:187–198.PubMedGoogle Scholar
  5. 5.
    Stone, T.W. 1979. Amino acids as neurotransmitters of corticofugal neurons in the rat; a comparison of glutamate and aspartate. Br. J. Pharmacol. 67:545–551.PubMedGoogle Scholar
  6. 6.
    Fonnum, F. 1978. Comments on localization of neurotransmitter in the basal ganglia. In Amino Acids as Neurotransmitter, F. Fonnum, Ed. pp. 143–153, Plenum Press, New York.Google Scholar
  7. 7.
    Bromberg, M.B., Penney, Jr., J.B., Young, A.B., and Stephenson, B.S. 1980. Evidence for glutamate as the neurotransmitter of corticothalamic and corticorubral pathways. Neurology (N.Y.) 30:396.Google Scholar
  8. 8.
    Thangnipon, W., and Stone-Mathisen, J. 1981. K+-Evoked Ca2+-dependent release ofd-[3H]aspartate from terminals of the corticpontine pathways. Neurosci. 23:181–186.Google Scholar
  9. 9.
    Reubi, J.C., and Cuenod, M. 1979. Glutamate release in vitro from corticstrial terminals. Brain Res. 176:185–188.PubMedGoogle Scholar
  10. 10.
    Young, A.B., Bromberg, M.B., and Penney, Jr. J.B. 1981. Decreased glutamate uptake in subcortical areas deafferentiated by sensorimotor cortical ablation in the cat. J. Neurosci. 1:241–249.PubMedGoogle Scholar
  11. 11.
    Klüver, H., and Barrera, E. 1954. On the use of azaporphin derivatives (phthalo-cyanines) in staining nervous tissue. J. Physiol. 37:631–633.Google Scholar
  12. 12.
    Rossier, J., Bauman, A., and Benda, P. 1973. Inproved purification of rat brain choline acetyltransferase. FEBS lett. 32:631–633.Google Scholar
  13. 13.
    Fonnum, F. 1969. Radiochemical microassays for the determination of choline acetyltransferase and acetylcholinesterase activities. Biochem. J. 115:465–475.PubMedGoogle Scholar
  14. 14.
    Lowry, O.H., Rosebrough, N.J., Farr, A.L., and Randall, R. 1951. Protein measurements with Folin phenol reagent. J. Biol. Chem. 193:265–275.PubMedGoogle Scholar
  15. 15.
    Ryan, T.A. 1959. Multiple comparisons in psychological research. Psychol. Bull. 56:26–47.PubMedGoogle Scholar
  16. 16.
    Nagata, Y., Okuya, M., Watanabe, R., and Honda, M. 1982. Regional distribution of cholinergic neurons in human spinal cord transection in patients with and without motor neuron disease. Brain Res. 244:223–229.PubMedGoogle Scholar
  17. 17.
    Cotman, C.W., and Hamberger, A. 1977. Glutamate as a CNS neurotransmitter: properties of release, inactivation and biosynthesis. Pages 379–412,in F. Fonnum (ed.), Amino Acids as Chemical Transmitters, Plenum Press, New York.Google Scholar
  18. 18.
    Curtis, D.R. 1979. Problems in the evaluation of glutamate as a central nervous system transmitter. Pages 163–175,in L.J. Filer, S. Garattini, M.R. Kare, W.A. Reynolds, and R.J. Wurtman (eds.), Glutamic Acid: Advances in Biochemistry and Physiology, Raven Press, New York.Google Scholar
  19. 19.
    Fagg, G.E., Jordan, C.C., and Webster, R.A. 1978. Descending fiber-mediated release of endogenous glutamate and glycine from the perfused cat spinal cord. Brain Res. 158:159–170.Google Scholar
  20. 20.
    Young, A.B., Penny, J.B., Dauth, G.W., and Gilman, S. 1983. Glutamate or aspartate as possible neurotransmitter of cerebral corticofugal fibers in the monkey. Neurology. 33:1513–1516.PubMedGoogle Scholar
  21. 21.
    Potashner, S.J., and Dymczyk, L. 1986. Amino acid levels in the guinea pig gray matter after axotomy of primary sensory and descending tracts. J. Neurochem. 47:412–422.PubMedGoogle Scholar
  22. 22.
    Young, A.B., Oster-Granite, M.L., Hemden, R.M., and Snyder, S.H. 1974. Glutamic acid; selective depletion by viralinduced granule cell loss in hamster cerebellum. Brain Res. 731:1–13.Google Scholar

Copyright information

© Plenum Publishing Corporation 1993

Authors and Affiliations

  • Kimikazu Fujita
    • 1
  • Yutaka Nagata
    • 1
  • Kohichi Konno
    • 2
  • Tetsuo Kanno
    • 2
  • Kamaravelu Selvakumar
    • 2
  1. 1.Department of Physiology, School of MedicineFujita Health UniversityToyoake-shi, Aichi-kenJapan
  2. 2.Department of Neurosurgery, School of MedicineFujita Health UniversityToyoake, AichiJapan

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