Springer Nature is making SARS-CoV-2 and COVID-19 research free. View research | View latest news | Sign up for updates

The mode of synaptic linkage in the cerebro-ponto-cerebellar pathway investigated with intracellular recording from pontine nuclei cells of the cat


1. Intracellular potentials of pontine nuclei (PN) cells were recorded in cats anesthetized with pentobarbitone sodium. 2. Stimulation of the cerebellar nuclear regions or the brachium pontis induced an antidromic action potential composed of IS-SD spikes, after-depolarization and after-hyperpolarization. 3. Cerebellar stimulation produced EPSPs only in a few PN cells. 4. Activation of the corticopontine or pyramidal tract produced in all PN cells an EPSP built up from the unitary components with variable amplitudes and time courses. Paired or repetitive activation revealed a property of the frequency potentiation of the EPSP. 5. Unitary EPSPs also occurred spontaneously. A great majority of these spontaneous EPSPs were cerebral in origin, and had amplitudes and time courses comparable with those evoked by stimulation of the corticopontine or pyramidal tract. 6. The half-width versus time to peak relationship of these unitary EPSPs suggested a dendritic location of the synapses with variable distances from the soma. It is assumed that large, proximal synapses serve for efficient relay of signals while small, distal synapses for their integration.

This is a preview of subscription content, log in to check access.


  1. Allen, G.I., Korn, H., Oshima, T.: The mode of synaptic linkage in the cerebro-ponto-cerebellar pathway of the cat. I. Responses in the brachium pontis. Exp. Brain Res. 24, 1–14 (1975a)

  2. Allen, G.I., Korn, H., Oshima, T., Toyama, K.: Time course of pyramidal activation of pontine nuclei cells in the cat. Brain Res. 19, 291–294 (1970)

  3. Allen, G.I., Korn, H., Oshima, T., Toyama, K.: The mode of synaptic linkage in the cerebro-ponto-cerebellar pathway of the cat. II. Responses of single cells in the pontine nuclei. Exp. Brain Res. 24, 15–36 (1975b)

  4. Allen, G.I., Oshima, T., Toyama, K.: Unitary components in corticopontine activation of the cat. Brain Res. 35, 245–249 (1971)

  5. Allen, G.I., Toyama, K.: An Automatic DC-level compensation circuit for electrophysiology. IEEE Trans. Biochem. Engineer. BME-20, 58–60 (1973)

  6. Eccles, J.C.: The central action of antidromic impulses in motor nerve fibres. Pflügers Arch. ges. Physiol. 260, 385–415 (1955)

  7. Eccles, J.C.: The Physiology of Synapses, pp. 83–90, 103–110. Berlin-Heidelberg-New York: Springer 1964

  8. Eccles, J.C.: Circuits in the cerebellar control of movement. Proc. nat. Acad. Sci. (Wash.) 58, 336–343 (1967)

  9. Eccles, J.C.: The dynamic loop hypothesis of movement control. In: Information Processing in the Nervous System (ed. K.N. Leibovic), pp. 245–269. Berlin-Heidelberg-New York: Springer 1969

  10. Evarts, E.V.: Feedback and corollary discharge: A merging of the concepts. In: Central Control of Movement (ed. E.V. Evarts et al.). Neurosci. Res. Progr. Bull. 9, 86–112 (1971)

  11. Holländer, H., Brodal, P., Walberg, F.: Electronmicroscopic observations on the structure of the pontine nuclei and the mode of termination of the corticopontine fibres. An experimental study in the cat. Exp. Brain Res. 7, 95–110 (1969)

  12. Ito, M.: Neurophysiological aspects of the cerebellar motor control system. Internat. J. Neurol. 7, 162–176 (1970)

  13. Landgren, S., Phillips, C.G., Porter, R.: Minimal synaptic actions of pyramidal impulses in some alpha motoneurones of the baboon's hand and forearm. J. Physiol. (Lond.) 161, 91–111 (1962)

  14. Mendell, L.M., Henneman, E.: Terminals of single la fibers: Location, density, and distribution within a pool of 300 homonymous motoneurons. J. Neurophysiol. 34, 171–187 (1971)

  15. Mihailoff, G.A., King, J.S.: The basilar pontine gray of the opossum: A correlated light and electron microscopic analysis. J. comp. Neurol. 159, 521–552 (1975)

  16. Oscarsson, O.: Functional organization of spinocerebellar paths. In: Handbook of Sensory Physiology, Vol. II. Somatosensory System, (ed. A. Iggo), pp. 339–380. Berlin-Heidelberg-New York: Springer 1973

  17. Porter, R.: Early facilitation at corticomotoneuronal synapses. J. Physiol. (Lond.) 207, 733–745 (1970)

  18. Porter, R., Hore, J.: The time-course of minimal corticomotoneuronal excitatory postsynaptic potentials in lumbar motoneurons of the monkey. J. Neurophysiol. 32, 443–451 (1969)

  19. Ramón y Cajal, S.: Histologie du système nerveux de l'homme et des vertébrés. Vol. 1. pp. 960–978. Paris: A. Maloine 1909

  20. Rall, W.: Electrophysiology of a dendritic neuron model. Biophys. J. 2, 145–167 (1962)

  21. Rall, W.: Theoretical significance of dendritic trees for neuronal input-output relations. In: Neural Theory and Modeling (ed. R.F. Reiss), pp. 73–96. Stanford: Univ. Press 1964

  22. Rall, W.: Distinguishing theoretical synaptic potentials for different soma-dendritic distributions of synaptic input. J. Neurophysiol. 30, 1138–1168 (1967)

  23. Rall, W., Burke, R.E., Smith, T.G., Nelson, P.G., Frank, K.: Dendritic location of synapses and possible mechanisms for the monosynaptic EPSP in motoneurons. J. Neurophysiol. 30, 1169–1193 (1967)

  24. Sasaki, K., Kawaguchi, S., Shimono, T., Prelević, S.: Electrophysiological studies of the pontine nuclei. Brain Res. 20, 425–438 (1970)

  25. Tsukahara, N., Bando, T.: Red nuclear and interposate nuclear excitation of pontine nuclear cells. Brain Res. 19, 295–298 (1970)

  26. Tsukahara, N., Bando, T., Kiyohara, T.: The properties of the reverberating circuit in the brain. In: Neuroendocrine Control (eds. K. Yagi and S. Yoshida), pp. 3–26. Tokyo. Tokyo Univ. Press 1973

  27. Tsukahara, N., Korn, H., Stone, J.: Pontine relay from cerebral cortex to cerebellar cortex and nucleus interpositus. Brain Res. 10, 448–453 (1968b)

  28. Tsukahara, N., Murakami, F., Hultborn, H.: Electrical constants of neurons of the red nucleus. Exp. Brain Res. 23, 49–64 (1975)

  29. Uchizono, K.: Characteristics of excitatory and inhibitory synapses in the central nervous system of the cat. Nature (Lond.) 207, 642–643 (1965)

  30. Uchizono, K.: Inhibitory synapses on the stretch receptor neurone of the crayfish. Nature (Lond.) 214, 833–834 (1967a)

  31. Uchizono, K.: Synaptic Organization of the Purkinje cells in the cerebellum of the cat. Exp. Brain Res. 4, 97–113 (1967b)

  32. Vasilenko, D.A., Kostyuk, P.G.: Functional properties of interneurons monosynaptically activated by the pyramidal tract. J. Higher Nerv. Act. 16, 1046–1054 (1966), (In Russian)

  33. Walberg, F.: Elongated vesicles in terminal boutons of the central nervous system. A result of aldehyde fixation. Acta anat. (Basel) 65, 224–235 (1966)

  34. Walberg, F.: Morphological correlates of postsynaptic inhibitory processes. In: Structure and Function of Inhibitory Neuronal Mechanisms (eds. C. von Euler et al.), pp. 7–14. Oxford: Pergamon Press 1968

Download references

Author information

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Allen, G.I., Oshima, T. & Toyama, K. The mode of synaptic linkage in the cerebro-ponto-cerebellar pathway investigated with intracellular recording from pontine nuclei cells of the cat. Exp Brain Res 29, 123–136 (1977).

Download citation

Key words

  • Pontine nuclei cells
  • Unitary EPSPs
  • Synaptic organization
  • Cat