Summary
The nucleus raphe dorsalis of the cat was examined by serial section electron microscopy and the presence of vesicle-containing dendrites is reported. Such dendrites were divided into two classes according to their synaptic contact. Dendrites containing round and/or pleomorphic vesicles associated with a clear synaptic specialization which was generally intermediate between a Gray's type I or II were classified as presynaptic dendrites. These presynaptic dendrites were presynaptic to conventional dendrites and dendritic spines. In addition, some profiles containing a sparse population of vesicles which may be dendritic in nature were observed involved in serial synaptic arrangements. A second class of dendrites were characterized by the presence of vesicles which were never found associated with any synaptic membrane specialization. Commonly, the vesicles were densely packed and associated with unusual densities. Serial section analysis of these densities showed that they were not presynaptic dense projections. We suggest that the existence of vesicle-containing dendrites in the nucleus raphe dorsalis of the cat constitute the morphological support for the dendritic release of neurotransmitters.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Azmitia, E. C. (1978) The serotonin-producing neurons of the midbrain median and dorsal raphe nuclei.Handbook ofPsychopharmacology 9, 233–314.
Baraban, J. M. &Aghajanian, G. K. (1981) Noradrenergic innervation of serotonergic neurons in the dorsal raphe: demonstration by electron microscopic autoradiography.Brain Research 204, 1–11.
Beaudet, A. &Descarries, L. (1981) The fine structure of central serotonin neurons.Journal de Physiologie (Paris) 77, 193–203.
Belin, M. F., Aguera, M., Tappaz, M., McRaedegueurcé, A., Bobillier, P. &Pujol, J. F. (1979) GABA-accumulating neurons in the nucleus raphe dorsalis and periaqueductal gray in the rat: a biochemical and radioautographic study.Brain Research 170, 279–97.
Berman, A. L. (1968)The Brain Stem of the Cat: A Cytoarchitectonic Atlas with Stereotaxic Coordinates. Madison: The University of Wisconsin Press.
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.
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.
Chazal, G. &Ralston, H. J. (1985) Morphology and synaptic relationships of normal and serotonergic processes in cat raphe dorsalis: a fine structural serial analysis.Society for Neuroscience Abstracts 11, 1018.
Cummings, J. P. &Felten, D. L. (1979) A raphe dendrite bundle in the rabbit medulla.Journal of Comparative Neurology 183, 1–24.
Dahlstrom, 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.
Danner, H. &Pfister, C. (1980) Untersuchungen zur zytoarchitektonik des nucleus raphe dorsalis der ratte.Journal Fuer Hirnforschung 21, 655–64.
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.
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.
Famiglietti, E. V. &Peters, A. (1972) The synaptic glomerulus and the intrinsic neuron in the dorsal lateral geniculate nucleus of the cat.Journal of Comparative Neurology 144, 285–334.
Felten, D. L. &Cummings, J. P. (1979) The raphe nuclei of the rabbit brain stem.Journal of Comparative Neurology 187, 199–244.
Felten, D. L. &Harrigan, P. (1980) Dendrite bundles in nuclei raphe dorsalis and centralis superior of the rabbit: a possible substrate for local control of serotonergic neurons.Neuroscience Letters 16, 275–80.
Groves, P. M. &Linder, J. C. (1983) Dendro-dendritic synapses in substantia nigra: descriptions based on analysis of serial sections.Experimental Brain Research 49, 209–17.
Groves, P. M. &Wilson, C. J. (1980) Monoaminergic presynaptic axons and dendrites in rat locus coeruleus seen in reconstructions of serial sections.Journal of Comparative Neurology 193, 853–62.
Guldner, F. H. &Wolff, J. R. (1974) Dendro-dendritic synapses in the suprachiasmatic nucleus of the rat hypothalamus.Journal of Neurocytology 3, 245–50.
Hery, F., Faudon, M. &Ternaux, J. P. (1982) In vivo release of serotonin in two raphe nuclei (raphe dorsalis and magnus) of the cat.Brain Research Bulletin 8, 123–9.
Jouvet, M. (1974) The role of monoaminergic neurons in the regulation and function of sleep. InBasic Sleep Mechanisms (edited byPetre-Quadens, O. &Schlag, D. J.), pp. 207–36. New York: Academic Press.
Kapadia, S. E., De Lanerolle, N. C. &Lamotte, C. C. (1985) Immunocytochemical and electron microscopic study of serotonin neuronal organization in the dorsal raphe nucleus of the monkey.Neuroscience 15, 729–46.
Lieberman, A. R. &Webster, K. E. (1974) Aspects of the synaptic organization of intrinsic neurons in the dorsal lateral geniculate nucleus.Journal of Neurocytology 3, 677–710.
Møllgård, K. &Møller, M. (1975) Dendrodendritic gap junctions: a developmental approach.Advances in Neurology 12, 79–89.
Palay, S. L., Sotelo, C., Peters, A. &Orkand, P. M. (1968) The axon hillock and the initial segment.Journal of Cell Biology 38, 193–201.
Ralston, H. J., III &Herman, M. M. (1969) The fine structure of neurons and synapses in the ventrobasal thalamus of the cat.Brain Research 14, 77–97.
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 of Physiology (Paris) 77, 157–74.
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.
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.
Wang, R. Y. &Aghajanian, G. K. (1982) Correlative firing patterns of serotonergic neurons in rat dorsal raphe nucleus.Journal of Neuroscience 2, 11–16.
Wilson, C. P., Groves, P. M. &Fifkova, E. (1977) Monoaminergic synapses, including dendro-dendritic synapses in the rat substantia nigra.Experimental Brain Research 30, 161–74.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Chazal, G., Ohara, P.T. Vesicle-containing dendrites in the nucleus raphe dorsalis of the cat. A serial section electron microscopic analysis. J Neurocytol 15, 777–787 (1986). https://doi.org/10.1007/BF01625194
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF01625194