Somato-Dendritic Synapses in the Nucleus Reticularis Thalami of the Rat


In the reticular nucleus of the rat thalamus, about 30% of the synapses are brought about by the perikarya of parvalbumin-immunopositive neurons, which establish somato-dendritic synapses with large dendrites of nerve cells of specific thalamic nuclei. Although the parvalbumin-immunopositive presynaptic structures bear resemblance to goblet-like or calyciform axonal endings, electron microscopic immunocytochemistry and in situ hybridization revealed that these structures are parts of the perikaryal cytoplasm studded with synaptic vesicles. In about 15% of the somato-dendritic synapses, axons are seen to be in synaptic contact with the parvalbumin-immunoreactive perikaryon. Double immunohistochemical staining revealed that the parvalbumin immunoreactive presynaptic perikarya and dendrites contained GABA. It is assumed that the peculiar somato-dendritic synaptic complexes subserve the goal of filtration of impulses arriving at the reticular nucleus from various thalamic nuclei, thus processing them for further sampling.


  1. 1.

    Berry, D. J., Ohara, P. T., Jeffery, G., Lieberman, A. R. (1986) Are there connections between the thalamic reticular nucleus and the brainstem reticular formation? J. Comp. Neurol. 243, 347–362.

    CAS  Article  Google Scholar 

  2. 2.

    Carman, J. B., Cowan, W. M., Powell, T. P. S. (1964) Cortical connections of the thalamic reticular nucleus. J. Anat. (London) 98, 587–598.

    CAS  Google Scholar 

  3. 3.

    Carpenter, M. B., Sutin, J. (1983) Human Neuroanatomy. Williams and Wilkins, Baltimore, London, Los Angeles, Sidney, pp. 535–536.

    Google Scholar 

  4. 4.

    Csillik, B., Rakic, P., Tajti, J., Samsam, M., Vécsei, L., Knyihár-Csillik, E. (1996) Alterations of parvalbumin immunoreactivity in Goll’s nucleus and in thalamic nuclei after transection of the dorsal column: transganglionic regulation of a calcium-binding neuroprotein. Ann. Anat. Suppl. 178, 25.

    Article  Google Scholar 

  5. 5.

    Famigletti, E. V. jr. (1970) Dendro-dendritic synapses in the lateral geniculate nucleus of the cat. Brain Res. 20, 181–191.

    Article  Google Scholar 

  6. 6.

    Famigletti, E. V. jr., Peters, A. (1972) The synaptic glomerulus and the intrinsic neuron in the dorsal lateral geniculate nucleus of the cat. J. Comp. Neurol. 144, 285–334.

    Article  Google Scholar 

  7. 7.

    Fisher, S. K. (1972) A somato-somatic synapse between amacrine and bipolar cells in the cat retina. Brain Res. 43, 587–590.

    CAS  Article  Google Scholar 

  8. 8.

    Guillery, R. W. (1969) The organization of synaptic interconnections in the laminae of the dorsal lateral geniculate nucleus in the cat. Z. Zellforsch. 96, 1–38.

    CAS  Article  Google Scholar 

  9. 9.

    Harding, R. N. (1971) Dendro-dendritic synapses, including reciprocal synapses, in the ventro-lateral nucleus of the monkey thalamus. Brain Res. 34, 181–185.

    CAS  Article  Google Scholar 

  10. 10.

    Jones, E. G. (1975) Some aspects of the organization of the thalamic reticular complex. J. Comp. Neurol. 162, 285–308.

    CAS  Article  Google Scholar 

  11. 11.

    Jones, E. G., Rockel, A. J. (1971) The synaptic organization in the medial geniculate body of fibres ascending from the inferior colliculus. Z. Zellforsch. 113, 44–66.

    CAS  Article  Google Scholar 

  12. 12.

    Le Vay, S. (1971) On the neurons and synapses of the lateral geniculate nucleus of the monkey, and the effect of eye enucleation. Z. Zellforsch. 113, 396–419.

    Article  Google Scholar 

  13. 13.

    Lewis, D. A., Akil, M. (1998) Axon terminals of the chandelier class of cortical GABA neurons. Molecular Psychiatry 3, 466–467.

    Article  Google Scholar 

  14. 14.

    Lieberman, A. R. (1973) Neurons with presynaptic perikarya and presynaptic dendrites in the rat lateral geniculate nucleus. Brain Res. 59, 35–59.

    CAS  Article  Google Scholar 

  15. 15.

    Lieberman, A. R., Webster, K. E. (1972) Presynaptic dendrites and a distinctive class of synaptic vesicle in the rat dorsal lateral geniculate nucleus. Brain Res. 42, 196–200.

    CAS  Article  Google Scholar 

  16. 16.

    Lieberman, A. R., Webster, K. E. (1974) Aspects of the synaptic organization of intrinsic neurons in the dorsal lateral geniculate nucleus. An ultrastructural study of the normal and of the experimentally deafferented nucleus in the rat. J. Neurocytology 3, 677–710.

    CAS  Article  Google Scholar 

  17. 17.

    Morest, D. K. (1971) Dendrodendritic synapses of cells that have axons: the fine structure of the Golgi type II cell in the medial geniculate body of the cat. Z. Anat. Entwickl-Gesch. 133, 216–246.

    CAS  Article  Google Scholar 

  18. 18.

    Ohara, P. T., Lieberman, A. R., Hunt, S. P., Wu, J.-Y. (1983) Neural elements containing glutamic acid decarboxylase (GAD) in the dorsal lateral geniculate nucleus of the rat: immunohistochemical studies by light and electron microscopy. Neuroscience 8, 189–211.

    CAS  Article  Google Scholar 

  19. 19.

    Ohara, P. T., Lieberman, A. R. (1985) The thalamic reticular nucleus of the adult rat: experimental anatomical studies. J. Neurocytology 14, 365–411.

    CAS  Article  Google Scholar 

  20. 20.

    Ralston, H. J. III, Herman, M. H. (1969) The fine structure of neurons and synapses in the ventrobasal thalamus of the cat. Brain Res. 14, 77–97.

    Article  Google Scholar 

  21. 21.

    Scheibel, M. E., Scheibel, A. B. (1966) The organization of the nucleus reticularis thalami: a Golgi study. Brain Res. 1, 43–62.

    CAS  Article  Google Scholar 

  22. 22.

    Sétáló, G., Székely, G. (1967) The presence of membrane specializations indicative of somato-dendritic synaptic junctions in the optic tectum of the frog. Exp. Brain Res. 4, 237–242.

    Article  Google Scholar 

  23. 23.

    Wong, M. T. T. (1970) Somato-dendritic and dendro-dendritic synapses in the squirrel monkey lateral geniculate nucleus. Brain Res. 20, 135–139.

    CAS  Article  Google Scholar 

  24. 24.

    Wong-Riley, M. T. T. (1972) Neuronal and synaptic organization of the normal dorsal lateral geniculate nucleus of the squirrel monkey, Saimiri sciureus. J. Comp. Neurol. 144, 25–60.

    CAS  Article  Google Scholar 

Download references

Author information



Corresponding author

Correspondence to B. Csillik.

Additional information

Dedicated to Professor József Hámori on the occasion of his 70th birthday.

Rights and permissions

This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (, which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.

Reprints and Permissions

About this article

Cite this article

Csillik, B., Pálfi, Á., Gulya, K. et al. Somato-Dendritic Synapses in the Nucleus Reticularis Thalami of the Rat. BIOLOGIA FUTURA 53, 33–41 (2002).

Download citation


  • Thalamus
  • reticular nucleus
  • parvalbumin
  • GABA
  • somato-dendritic synapses