Advertisement

Experimental Brain Research

, Volume 19, Issue 4, pp 394–405 | Cite as

Crossed effects on central vestibular neurons in the horizontal canal system of the frog

  • S. Ozawa
  • W. Precht
  • H. Shimazu
Article

Summary

  1. 1.

    Neuronal discharges were recorded extracellularly in curarized frogs (Rana esculenta) with glassmicropipettes. Vestibular neurons, which were activated by ipsilateral horizontal angular acceleration and suppressed during deceleration (type 1) were found mainly in the medial part of the ventral vestibular nucleus.

     
  2. 2.

    In contrast to type 1 vestibular neuron of the cat, this type of neuron in the frog was not suppressed, but facilitated by electrical stimulation of the contralateral vestibular nerve, irrespective of stimulus intensity. In most cases the facilitation was subthreshold for producing full action potentials when single stimulation was applied.

     
  3. 3.

    Single shocks applied to the contralateral vestibular nerve evoked small negative field potentials (maximum peak amplitude, 300 μV) in the vestibular nucleus. The threshold for the potential was 2.5–3.0 times threshold for the field potential recorded in the vestibular nucleus on the stimulated side. The latency ranged from 5.0 to 8.0 msec.

     
  4. 4.

    Intracellular recordings were obtained from the neurons in the medial part of the ventral vestibular nucleus. These neurons exhibited monosynaptic EPSP in response to ipsilateral vestibular nerve stimulation. Following electrical stimulation of the contralateral vestibular nerve polysynaptic EPSPs were found with latencies between 5.0 and 10.0 msec and no IPSPs were detected.

     
  5. 5.

    The EPSPs induced by single supramaximal shocks to the contralateral vestibular nerve were in most cases not large enough to evoke full action potentials. In more than half of the cells recorded from, partial spikes were superimposed on the EPSPs.

     
  6. 6.

    In the vestibular neurons which send axons to the peripheral receptor organs, EPSPs were induced by stimulation of the contralateral vestibular nerve. There were no highly significant differences between the time courses of these EPSPs and those described in 4.

     

Key words

Frog vestibular neurons Type 1 response Crossed vestibular facilitation 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Baker, R.G., Mano, N., Shimazu, H.: Postsynaptic potentials in abduoens motoneurons induced by vestibular stimulation. Brain Res. 15, 577–580 (1969)Google Scholar
  2. Brookhart, J.M., Fadiga, E.: Potential fields initiated during monosynaptic activation of frog motoneurones. J. Physiol. (Lond.) 150, 633–655 (1960)Google Scholar
  3. Burlet, H.M. de: Zur vergleichenden Anatomie der Labyrinthinnervation. J. comp. Neurol. 47, 155–169 (1929)Google Scholar
  4. Cohen, B., Suzuki, J., Bender, M.B.: Eye movements from semicircular canal nerve stimulation in the cat. Ann. Otol. (St. Louis) 73, 153–169 (1964)Google Scholar
  5. Duensing, F., Schaefer, K.P.: Die Aktivität einzelner Neurone im Bereich der Vestibulariskerne bei Horizontalbeschleunigungen unter besonderer Berücksichtigung des vestibulären Nystagmus. Arch. Psychiat. Nervenkr. 198, 225–252 (1958)Google Scholar
  6. Goldberg, J.M., Fernandez, C.: Physiology of peripheral neurons innervating semicircular canals of the squirrel monkey. I. Resting discharge and response to constant angular accelerations. J. Neurophysiol. 34, 635–660 (1971)Google Scholar
  7. Groen, J.J., Löwenstein, O., Vendrik, A.J.H.: The mechanical analysis of the responses from the end-organs of the horizontal semicircular canal in the isolated elasmobranch labyrinth. J. Physiol. (Lond.) 117, 329–346 (1952)Google Scholar
  8. Grofová, I., Corvaja, N.: Commissural projection from the nuclei of termination of the VIIIth cranial nerve in the toad. Brain Res. 42, 189–195 (1972)Google Scholar
  9. Highstein, S.M., Ito, M., Tsuchiya, T.: Synaptic linkage in the vestibulo-ocular reflex pathway of rabbit. Exp. Brain Res. 13, 306–326 (1971)Google Scholar
  10. Kappers, C.U.A., Huber, G.C., Crosby, E.C.: The lateral line and acoustic systems. In: The comparative anatomy of the nervous system of vertebrates, including man, pp. 433–503. New York: The Macmillan Company 1936Google Scholar
  11. Kasahara, M., Mano, N., Oshima, T., Ozawa, S., Shimazu, H.: Contralateral short latency inhibition of central vestibular neurons in the horizontal canal system. Brain Res. 8, 376–378 (1968)Google Scholar
  12. Kasahara, M., Uchino, Y.: Selective mode of commissural inhibition induced by semicircular canal afferents on secondary vestibular neurons in the cat. Brain Res. 34, 366–369 (1971)Google Scholar
  13. Llinás, R., Precht, W.: The inhibitory vestibular efferent system and its relation to the cerebellum in the frog. Exp. Brain Res. 9, 16–29 (1969)Google Scholar
  14. Löwenstein, O., Sand, A.: The mechanism of the semicircular canal. A study of the responses of single fiber preparations to angular accelerations and rotation at constant speed. Proc. roy. Soc. B. 129, 256–275 (1940)Google Scholar
  15. Mano, N., Oshima, T., Shimazu, H.: Inhibitory commissural fibers interconnecting the bilateral vestibular nuclei. Brain Res. 8, 378–382 (1968)Google Scholar
  16. Precht, W., Baker, R.G.: Synaptic organization of the vestibulo-trochlear pathway. Exp. Brain Res. 14, 158–184 (1972)Google Scholar
  17. Precht, W., Llinás, R., Clarke, M.: Physiological responses of frog vestibular fibers to horizontal angular rotation. Exp. Brain Res. 13, 378–407 (1971)Google Scholar
  18. Precht, W., Richter, A., Ozawa, S., Shimazu, H.: Intracellular study of frog's vestibular neurons in relation to the labyrinth and spinal cord. Exp. Brain Res. 19, 377–393 (1974)Google Scholar
  19. Shimazu, H., Precht, W.: Tonic and kinetic responses of cat's vestibular neurons to horizontal angular acceleration. J. Neurophysiol. 28, 991–1013 (1965)Google Scholar
  20. Shimazu, H., Precht, W.: Inhibition of central vestibular neurons from the contralateral labyrinth and its mediating pathway. J. Neurophysiol. 29, 467–492 (1966)Google Scholar
  21. Steinhausen, W.: Über den Nachweis der Bewegung der Cupula in der intakten Bogengangsampulle des Labyrinthes bei der natürlichen rotatorischen und calorischen Reizung. Pflügers Arch. ges. Physiol. 228, 322–328 (1931)Google Scholar
  22. Steinhausen, W.: Über die Beobachtung der Cupula in den Bogengangsampullen des Labyrinthes des lebenden Hechts. Pflügers Arch. ges. Physiol. 232, 500–512 (1933)Google Scholar
  23. Szentágothai, J.: The elementary vestibulo-ocular reflex arc. J. Neurophysiol. 13, 395–407 (1950)Google Scholar
  24. Thomas, R.C., Wilson, V.J.: Precise localization of Renshaw cells with a new marking technique. Nature (Lond.) 206, 211–213 (1965)Google Scholar
  25. Van Egmond, A.A.J., Groen, J.J., Jonkees, L.B.W.: The mechanics of the semicircular canal. J. Physiol. (Lond.) 110, 1–17 (1949)Google Scholar

Copyright information

© Springer-Verlag 1974

Authors and Affiliations

  • S. Ozawa
    • 1
  • W. Precht
    • 1
  • H. Shimazu
    • 1
    • 2
  1. 1.Neurobiologische AbteilungMax-Planck-Institut für HirnforschungFrankfurt(FRG)
  2. 2.Department of NeurophysiologyInstitute of Brain Research, School of Medicine, University of TokyoTokyo(Japan)

Personalised recommendations