Experimental Brain Research

, Volume 29, Issue 3–4, pp 531–539 | Cite as

Electron microscopic identification of postsynaptic dorsal root terminals: a possible substrate of dorsal root potentials in the frog spinal cord

  • G. Székely
  • B. Kosaras
Article
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Summary

Dorsal root fibers were labeled with cobaltous chloride iontophoresis for electron microscopic investigations. In the base of the dorsal horn, where most of the coarser collaterals of dorsal root fibers terminate, many dorsal root terminals were found in postsynaptic relation to synapsing profiles. According to their morphological characteristics, three kinds of presynaptic terminals could be discerned in these complex synapses: axon terminals with spheric vesicles, axon terminals with flattered vesicles and presynaptic dendrites. These latter terminals contained relatively few flattened vesicles accumulated adjacent to a short synaptic articulation surface, and they were rich in cytoplasmic organelles. The functional significance of these structural specializations in the mediation of dorsal root potentials and recurrent inhibition is discussed.

Key words

Cobalt labeling Axo-axonic synapses Presynaptic dendrites Spinal cord Frog 
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Copyright information

© Springer-Verlag 1977

Authors and Affiliations

  • G. Székely
    • 1
  • B. Kosaras
    • 2
  1. 1.Department of AnatomyUniversity Medical School DebrecenHungary
  2. 2.Department of AnatomyUniversity Medical School PécsHungary

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