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Synaptic organization of the nucleus raphe dorsalis of the cat

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Journal of Neurocytology

Summary

This electron microscopic study describes the different types of synaptic terminals found in the nucleus raphe dorsalis of the adult cat. Serial section analysis was used extensively to confirm the nature of the synaptic contact established by the various classes of terminals.

Five different classes of terminals are identified according to the shape and packing density of the synaptic vesicles and type of contact they establish. The most common class (RDI-type) contains densely packed, round, agranular synaptic vesicles and establishes asymmetrical synaptic contacts. A second class (RDII-type) also contains spherical synaptic vesicles, but establishes symmetrical synaptic contacts with dendrites of all sizes. Most of the terminals in these two classes contain a few dense-cored synaptic vesicles, but a small sub-group contains many dense-cored vesicles. A third, less frequent, class (RSI-type) contains sparsely packed spherical synaptic vesicles and the majority of these terminals have asymmetrical contacts. A fourth terminal class contains pleomorphic synaptic vesicles (P-type), contacts dendrites of all sizes, and usually establishes symmetrical synaptic contacts. Finally, boutons thought to be the vesicle-filled excrescences of dendrites (postsynaptic dendrites) are found and in some cases the dendritic origin of these profiles was confirmed by serial sectioning. Such boutons containing pleomorphic vesicles are presynaptic to other such dendrites as well as conventional dendrites, and are postsynapticto the other terminal types described.

Somata within the nucleus exhibit somatic spines but receive few synaptic contacts. Most axo-somatic terminals contain either round or pleomorphic vesicles and have postsynaptic thickenings intermediate to the symmetric and asymmetric types.

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References

  • Azmitia, E. C. (1978) The serotonin-producing neurons of the midbrain median and dorsal raphe nuclei.Handbook of Psychopharmacology 9, 233–14.

    Google Scholar 

  • Baraban, J. M. &Aghajanian, G. K. (1981) Norad-renergic innervation of serotonergic neurons in the dorsal raphe: demonstration by electron microscopic autoradiography.Brain Research 204, 1–11.

    Google Scholar 

  • Beitz, A. J. (1982) The organization of afferent projections to the midbrain periaqueductal gray of the rat.Neuroscience 7, 133–59.

    Google Scholar 

  • Berman, A. L. (1968)The Brain Stem of the Cat: A Cytoarchitectonic Atlas with Stereotaxic Coordinates. Madison: The University of Wisconsin Press.

    Google Scholar 

  • Besson, J-M., Guilbaud, G., Abdelmoumene, A. &Chaouch, A. (1982) Physiologie de la nociception.Journal de physiologie (Paris) 78, 7–107.

    Google Scholar 

  • Bobillier, P., Petitjean, F., Salvert, D., Ligier, M. &Seguin, S. (1975) Differential projections of the nucleus raphe dorsalis and nucleus raphe centralis as revealed by autoradiography.Brain Research 85, 205–10.

    Google Scholar 

  • Chan-Palay, V. (1982) Serotonin neurons and their axons in the raphe dorsalis of rat and rhesus monkey: demonstration by high resolution autoradiography with 3H-serotonin. InCytochemical Methods in Neuroanatomy (edited byChan-Palay, V. &Palay, S. L.), pp. 357–86. New York: Alan R. Liss.

    Google Scholar 

  • Chazal, G. &Ohara, P. T. (1986) Vesicle-containing dendrites in the nucleus raphe dorsalis of the cat. A serial electron microscopic analysis.Journal of Neurocy-tology 15, 777–87.

    Google Scholar 

  • Chazal, G. &Ralston III, H. J. (1987) Serotonin-containing structures in the nucleus raphe dorsalis of the cat: an ultrastructural analysis of dendrites, presynaptic dendrites and axon terminals.Journal of Comparative Neurology 259, 317–29.

    Google Scholar 

  • Clements, J. R., Beitz, A. J., Fletcher, T. F. &Mullett, M. A. (1985) Immunocytochemical localization of serotonin in the rat periaqueductal gray: a quantitative light and electron microscopic study.Journal of Comparative Neurology 236, 60–70.

    Google Scholar 

  • Colonnier, M. (1968) Synaptic patterns on different cell types in the different laminae of the cat visual cortex. An electron microscope study.Brain Research 9, 268–87.

    Google Scholar 

  • Dahlström, A. &Fuxe, K. (1964) Evidence for the existence of monoamine-containing neurons in the central nervous system. I. Demonstration of monoamines in the cell bodies of brain stem neurons.Acta physiologica scandinavica 62, Suppl. 232, 1–55.

    Google Scholar 

  • Descarries, L., Watkins, K. C., Garcia, S. &Beaudet, A. (1982) The serotonin neurons in nucleus raphe dorsalis of adult rat: a light and electron microscope radioautographic study.Journal of Comparative Neurology 207, 239–54.

    Google Scholar 

  • Diaz-Cintra, S., Cintra, L., Kemper, T., Resnick, O. &Morgane, P. J. (1981) Nucleus raphe dorsalis: a morphometric Golgi study in rats of three age groups.Brain Research 207, 1–16.

    Google Scholar 

  • Famiglietti, E. V. (1970) Dendro-dendritic synapses in the lateral geniculate nucleus of the cat.Brain Research 20, 181–91.

    Google Scholar 

  • Felten, D. L. &Cummings, J. P. (1979) The raphe nuclei of the rabbit brain stem.Journal of Comparative Neurology 187, 199–244.

    Google Scholar 

  • Felten, D. L. &Sladek, J. R. (1983) Monoamine distribution in primate brain. V. Monoaminergic nuclei: anatomy, pathways and local organization.Brain Research Bulletin 10, 171–284.

    Google Scholar 

  • Gamrani, H. &Calas, A. (1980) Cytochemical, stereological radioautographic studies of rat raphe neurons.Mikroskopie 36, 1–11.

    Google Scholar 

  • Gray, E. G. (1959) Axo-somatic and axo-dendritic synapses of the cerebral cortex: an electron microscope study.Journal of Anatomy 93, 420–33.

    Google Scholar 

  • Gioia, M., Tredici, G. &Bianchi, R. (1983) The ultrastructure of the periaqueductal gray matter of the cat.Submicroscopic Cytology 15, 1013–26.

    Google Scholar 

  • Jacobs, B. L., Cannon, P. J. &Azmitia, E. C. (1984) Atlas of serotonergic cell bodies in the cat brainstem: an immunocytochemical analysis.Brain Research Bulletin 13, 1–31.

    Google Scholar 

  • Jones, E. G. (1985)The Thalamus. New-York: Plenum Press.

    Google Scholar 

  • Kalen, P., Karlson, M. &Wiklund, L. (1985) Possible excitatory amino acid afferents to nucleus raphe dorsalis of the rat investigated with retrograde wheat germ agglutinin and D-(3H)aspartate tracing.Brain Research 360, 285–97.

    Google Scholar 

  • Kapadia, S. E., De Lanerolle, N. C. &La Motte, C. C. (1985) Immunocytochemical and electron microscopic study of serotonin neuronal organization in the dorsal raphe nucleus of the monkey.Neuroscience 15, 729–46.

    Google Scholar 

  • Kawasaki, T. &Sato, Y. (1981) Afferent projections to the caudal part of the dorsal nucleus of the raphe in cats.Brain Research 211, 439–44.

    Google Scholar 

  • Liu, R. P. C. &Hamilton, B. L. (1980) Neurons of the periaqueductal gray matter as revealed by Golgi study.Journal of Comparative Neurology 189, 403–18.

    Google Scholar 

  • Mosko, S. S., Haubrich, D. &Jacobs, B. L. (1977) Serotonergic afferents to the dorsal raphe nucleus: evidence from HRP and synaptosomal uptake studies.Brain Research 119, 269–90.

    Google Scholar 

  • Moss, M. S. &Basbaum, A. I. (1983a) The fine structure of the caudal periaqueductal gray of the cat: morphology and synaptic organization of normal and immunoreactive enkephalin-labeled profiles.Brain Research 289, 27–43.

    Google Scholar 

  • Moss, M. S. &Basbaum, A. I. (1983b) The peptidergic organization of the cat periaqueductal gray. II. The distribution of immunoreactive substance P and vasoactive intestinal polypeptide.Journal of Neuroscience 3, 1437–49.

    Google Scholar 

  • Nanopoulos, D., Belin, M. F., Maitre, M., Vincendon, G. &Pujol, J. F. (1982) Immunocytochemical evidence for the existence of GABAergic neurons in the nucleus raphe dorsalis. Possible existence of neurons containing serotonin and GABA.Brain Research 232, 375–89.

    Google Scholar 

  • Park, M. R., Imai, H. &Kitai, S. T. (1982) Morphology and intracellular responses of an identified dorsal raphe projection neuron.Brain Research 240, 321–6.

    Google Scholar 

  • Sakai, K., Salvert, D., Touret, M. &Jouvet, M. (1977) Afferent connections of the nucleus raphe dorsalis in the cat as visualized by the horseradish peroxidase technique.Brain Research 137, 11–35.

    Google Scholar 

  • Steinbusch, H. W. M., Nieuwenhuys, R., Verhofstad, A. A. J. &Van Der Kooy, D. (1981) The nucleus raphe dorsalis of the rat and its projection upon the caudatoputamen. A combined cytoarchitectonic, immunohistochemical and retrograde transport study.Journal de physiologie (Paris) 77, 157–74.

    Google Scholar 

  • Taber, E. (1961) The cytoarchitecture of the brain stem of the cat. I. Brain stem nuclei of cat.Journal of Comparative Neurology 116, 27–69.

    Google Scholar 

  • Takeuchi, Y., Kimura, H. &Sano, Y. (1982) Immunohistochemical demonstration of the distribution of serotonin neurons in the brainstem of the rat and cat.Cell and Tissue Research 224, 247–67.

    Google Scholar 

  • Uhl, G. R., Goodman, R. R., Kuhar, M. J., Childers, S. R. &Snyder, S. H. (1979) Immunohistochemical mapping of enkephalin-containing cell bodies, fibers and nerve terminals in the brain stem of the rat.Brain Research 166, 75–94.

    Google Scholar 

  • Valdivia, O. (1971) Methods of fixation and the morphology of synaptic vesicles.Journal of Comparative Neurology 142, 257–74.

    Google Scholar 

  • Wang, R. Y. &Aghajanian, G. K. (1977) Antidromically identified serotonergic neurons in the rat midbrain raphe: evidence for collateral inhibition.Brain Research 132, 186–93.

    Google Scholar 

  • Wiklund, L., Leger, L. &Persson, M. (1981) Monoamine cell distribution in the cat brain stem. A fluorescence histochemical study with quantification of indolaminergic and locus coeruleus cell groups.Journal of Comparative Neurology 203, 613–47.

    Google Scholar 

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Author notes

  1. G. Chazal

    Present address: INSERM, U-6, 280 Bd. Ste Marguerite, 13009, Marseille, France

Authors and Affiliations

  1. Anatomy Department, University of California, 94143, San Francisco, San Francisco, CA, USA

    G. Chazal & P. T. Ohara

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  1. G. Chazal
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  2. P. T. Ohara
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Chazal, G., Ohara, P.T. Synaptic organization of the nucleus raphe dorsalis of the cat. J Neurocytol 16, 667–679 (1987). https://doi.org/10.1007/BF01637658

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  • DOI: https://doi.org/10.1007/BF01637658

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