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Investigation of synaptic connections between primary afferents and motoneurons in the frog spinal cord by intracellular injection of horseradish peroxidase

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Abstract

Parallel recordings of potentials from primary afferent fibers and motoneurons connected monosynaptically with them were obtained in experiments on the isolated, perfused frog spinal cord and this was followed by intra-axonal and intracellular injection of horseradish peroxidase. Terminals of the primary afferent fibers were shown to reach the motor nuclei of the ventral horn, and one fiber could form contacts with several motoneurons. Synapses formed by afferent terminals were found not only on distal, but also on proximal segments of dendrites and also on motoneuron bodies. Synapses were most numerous on the proximal segments of the dendrites and branches of the second-third orders. Recurrent axon collaterals of motoneurons forming synapses with dendrites were found.

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Authors
  1. M. V. Motorina
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  2. Z. A. Tamarova
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  3. A. I. Shapovalov
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  4. B. I. Shiryaev
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Additional information

I. M. Sechenov Institute of Evolutionary Physiology and Biochemistry, Academy of Sciences of the USSR, Leningrad. Translated from Neirofiziologiya, Vol. 14, No. 1, pp. 60–68, January–February, 1982.

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Motorina, M.V., Tamarova, Z.A., Shapovalov, A.I. et al. Investigation of synaptic connections between primary afferents and motoneurons in the frog spinal cord by intracellular injection of horseradish peroxidase. Neurophysiology 14, 48–56 (1982). https://doi.org/10.1007/BF01058819

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  • DOI: https://doi.org/10.1007/BF01058819

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