Experimental Brain Research

, Volume 6, Issue 1, pp 1–18

A pharmacological study of the depression of spinal neurones by glycine and related amino acids

  • D. R. Curtis
  • L. Hösli
  • G. A. R. Johnston
Article

DOI: 10.1007/BF00235443

Cite this article as:
Curtis, D.R., Hösli, L. & Johnston, G.A.R. Exp Brain Res (1968) 6: 1. doi:10.1007/BF00235443

Summary

An analysis has been made in anaesthetised cats of the depression by glycine and related amino acids of the firing of spinal dorsal horn interneurones, Renshaw cells and cortical neurones. In general, electrophoretically administered glycine was a more potent depressant of interneurones than GABA. The reverse was true for cortical neurones, whereas these two amino acids were approximately equally effective upon Renshaw cells. Strychnine blocked the depressant action of α- and β-amino acids, but not that of γ- and higher ω-amino acids. Only convulsants having a strychnine-like effect on spinal post-synaptic inhibition blocked the action of glycine. The depression of spinal neurones produced by glycine or GABA was not affected by structural analogues of glycine and GABA that were not depressants, or by substances influencing amino acid transport systems. Some evidence was obtained for the enzymic inactivation of electrophoretically administered glycine in spinal tissue. The results are discussed in terms of the involvement of a glycine-like amino acid as a major spinal inhibitory transmitter.

Key Words

GlycineGABASpinal postsynaptic inhibitionStrychnineEnzyme inhibition

Copyright information

© Springer-Verlag 1968

Authors and Affiliations

  • D. R. Curtis
    • 1
  • L. Hösli
    • 1
  • G. A. R. Johnston
    • 1
  1. 1.Department of PhysiologyAustralian National UniversityCanberraAustralia