Summary
Two synapsing and impregnated neurons in the rat visual cortex have been examined by a combined Golgi-electron microscope technique in which the Golgi precipitate is replaced by gold particles. One of the neurons is a stellate cell with smooth dendrites and a well impregnated axon, while the other is a layer III pyramidal neuron. Light microscopy showed some boutons from the axonal plexus of the stellate cell closely apposed to the soma and dendrites of the pyramid and it was predicted that synapses were present at these sites. An electron microscopic examination of serial thin sections, in which the profiles of the impregnated neurons are marked by their content of gold particles, showed most of these predicted synapses to exist. Indeed, axon terminals of the stellate cell formed five symmetric synapses with the cell body of the pyramid, one with the apical dendritic shaft and three with basal dendrites. Reasons are given for believing these synapses to be inhibitory.
In addition, it was found that one of the axon terminals of the stellate cell synapsed with one of that cell's own dendrites. The significance of this finding is discussed.
Similar content being viewed by others
References
Bishop, P. O., Coombs, J. S. &Henry, G. H. (1971) Responses to contours: spatio-temporal aspects of excitation in the receptive fields of simple striate neurons.Journal of Physiology 219, 625–59.
Eccles, J. C. (1966) Cerebral synaptic mechanisms. InBrain and Conscious Experience (edited byEccles, J. C.), pp. 24–58. New York: Springer-Verlag.
Fairén, A., Peters, A. &Saldanha, J. (1977) A new procedure for examining Golgi impregnated neurons by light and electron microscopy.Journal of Neurocytology 6, 311–37.
Feldman, M. L. &Peters, A. (1978) The forms of non-pyramidal neurons in rat visual cortex.Journal of Comparative Neurology 179, 761–94.
Güldner, F.-H. &Wolff, J. R. (1978) Self-innervation of dendrites in the rat suprachiasmatic nucleus.Experimental Brain Research 32, 77–82.
Jones, E. G. (1975) Varieties and distribution of non-pyramidal cells in the somatic sensory cortex of the squirrel monkey.Journal of Comparative Neurology 160, 205–68.
Krieg, W. J. S. (1946) Connections of the cerebral cortex. I. Albino rat. A. Topography of the cortical areas.Journal of Comparative Neurology 84, 221–75.
Levay, S. (1973) Synaptic patterns in the visual cortex of the cat and monkey. Electron microscopy of Golgi preparations.Journal of Comparative Neurology 150, 53–86.
O'Leary, J. L. (1941) Structure of the area striata of the cat.Journal of Comparative Neurology 75, 131–64.
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.
Parnavelas, J. G., Sullivan, K., Lieberman, A. R. &Webster, K. E. (1977) Neurons and their synaptic organization in the visual cortex of the rat. Electron microscopy of Golgi preparations.Cell and Tissue Research 183, 499–517.
Peters, A. &Fairén, A. (1978) Smooth and sparsely-spined stellate cells in the visual cortex of the rat: A study using a combined Golgi-electron microscope technique.Journal of Comparative Neurology 181, 129–72.
Peters, A., Feldman, M. &Saldanha, J. (1976) The projection of the lateral geniculate nucleus to area 17 of the rat cerebral cortex. II. Terminations upon neuronal perikarya and dendritic shafts.Journal of Neurocytology 5, 85–107.
Peters, A. &Kaiserman-Abramof, I. R. (1970) The small pyramidal neuron of rat cerebral cortex. The perikaryon, dendrites and spines.American Journal of Anatomy 127, 321–56.
Peters, A., Proskauer, C. C., Feldman, M. L. &Kimerer, L. (1979) The projection of the lateral geniculate nucleus to area 17 of the rat cerebral cortex. V. Degenerating axon terminals synapsing with Golgi impregnated neurons.Journal of Neurocytology 8, 331–57.
Peters, A., Proskauer, C. C. &Kaiserman-Abramof, I. R. (1968) The small pyramidal neuron of the rat cerebral cortex: The axon hillock and initial segment.Journal of Cell Biology 39, 604–19.
Reese, T. S. &Karnovsky, M. J. (1967) Fine structural localization of a blood-brain barrier to exogenous peroxidase.Journal of Cell Biology 34, 207–18.
Ribak, C. E. (1978) Aspinous and sparsely-spinous stellate neurons in the visual cortex of rats contain glutamic acid decarboxylase.Journal of Neurocytology 7, 461–78.
Schober, W. &Winkelmann, E. (1975) Der visuelle Kortex der Ratte. Cytoarchitektonik und sterotaktische Parameter.Zeitschrift für mikroskopisch-anatomische Forschung 89, 431–46.
Somogyi, P. (1977) A specific ‘axo-axonal’ interneuron in the visual cortex of the rat.Brain Research 136, 345–50.
Toyama, K., Maekawa, K. &Takeda, T. (1977) Convergence of retinal inputs onto visual cortical cells: I. A study of the cells monosynaptically excited from the lateral geniculate body.Brain Research 137, 207–20.
Toyama, K., Matsunami, K., Ohno, T. &Tokashiki, S. (1974) An intracellular study of neuronal organization in the visual cortex.Experimental Brain Research 21, 45–66.
Valverde, F. (1970) The Golgi method. A tool for comparative structural analyses. InContemporary Research Methods in Neuroanatomy (edited byNauta, W. J. H. andEbbesson, S. O. E.), pp. 11–31. New York: Springer-Verlag.
Valverde, F. (1978) The organization of Area 18 in the monkey. A Golgi study.Anatomy and Embryology 154, 305–34.
Van Der Loos, H. &Glaser, E. M. (1972) Autapses in neocortex cerebri: synapses between a pyramidal cell's axon and its own dendrites.Brain Research 48, 355–60.
Vaughan, D. W. &Peters, A. (1973) A three dimensional study of layer I of the rat parietal cortex.Journal of Comparative Neurology 149, 355–70.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Peters, A., Proskauer, C.C. Synaptic relationships between a multipolar stellate cell and a pyramidal neuron in the rat visual cortex. A combined Golgi-electron microscope study. J Neurocytol 9, 163–183 (1980). https://doi.org/10.1007/BF01205156
Received:
Revised:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF01205156