Sinapsi dendro-dendritiche ed altre sinapsi in sferule riaggregate e coltivate in vitro di bulbi olfattori di embrione di pollo

Stefanelli, Alberto ; Cataldi, Emilia ; Ieradi, Luisanna

Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti, Tome 60 (1976), p. 653-660 / Harvested from Biblioteca Digitale Italiana di Matematica

Résumé

Well differentiated neurons and glial cells are visible within globular structures of about $200 \mu$ diameter, obtained from a aggregation of disaggregated olfactory bulbs of chicken embryos, 10 days' incubation old, and cultivated in the “rotating shaker” for 20 days. Particularly recognizable are mitral cells and granule cells (amacrine). Electron microscopy reveals different kinds of synaptic profiles: axo-dendritic, axo-somatic and dendro-dendritic. Of particular interest is the finding in the cultivated globules of this last type of synapse between mitral cell dendrites and dendrites of the granule cell, because it is clearly evident that this type of synapse is not produced here by any excitement derived from peripheric input (from fila olfactoria) in this case completely lacking, as it is proposed by physiological works, but is the expression of an intrinsic capability of the coupled neurons, acquired at the moment of the specific hystogenetic determination at an embryonal stage, earlier than the stage of disaggregation. Many peculiar morphological data of these dendro-dentritic synapses are described and discussed.

Détail

Publié le : 1976-12-01

Bibliographie

Andres, K. M. (1965) - Der Feinbau der Bulbus olfactorius der Ratte unter besonderer berücksichtigung der synaptischen Verbindungen, «Z. Zellf.», 65, 530-561.

Andres, K. H. (1970) - Anatomy and ultrastructure of the olfactory bulb in Fish, Amphibia, Reptiles, Birds und Mammals. In «Taste und smell in Vertebrates», Ciba Found. Symp., Churchill, London.

Colonnier, M. (1968) - Synaptic patterns on different cell types in the different laminae of the cat visual cortex, «Brain Res», 9, 268—287.

Gray, E. G. (1959) - Axo-somatic and axo-dendritic synapses of the cerebral cortex, «J. Anat.» 93, 420-433.

Hartline, H. K., Wagner, H. G. e Ratliff, F.(1956)- Inhibitions in the eye of Limulus, «J. gen. Physiol.», 39, 651-673.

Hinds, J. W. (1970) - Reciprocal and serial dendro-dendritic synapses in the glomerular layer of the rat olfactory bulb, «Brain Res.», 17, 530-534.

Hirata, Y. (1964) - Some observations on the fine structure of the synapses in the olfactory bulb with particular reference to atypical synaptic configurations, «Arch. Histol Jap.», 24, 293-302.

Lieberman, A. R. (1972) - Presynaptic dendrites and a distinctive class of synaptic vesicle, «Brain Res.», 42, 196-200.

Macleod, P. (1971) - Structure and function of the higher olfactory centers. In: «Olfaction», Ed. Lloid M. Beidler. Springer-Verlag, Berlino.

Morest, D. K. (1971) - Dendrodendritic synapses of cells that have axons, «Z. Anat. Entw.», 133, 216-246.

Price, J. L. e Powell, T. P. S. (1970) - The synaptology of the granule cells of olfactory bulb, «J. Cell. Sc.», 7, 125-155.

Rall, W., Shepherd, G. M., Reese, T.S. e Brightman, M.W. (1966) - Dendro-dendritic synaptic pathways for inhibition in the olfactory bulb, «Exper. neurol.», 14, 44-56.

Rall, W. e Shepherd, G.M. (1968) - Theoretical reconstruction of field potentials and dendrodendritic synaptic interconnections in olfactory bulb, «J. Neurophysiol.», 31, 884-915.

Ramón-Moliner, E. (1973) - Presynaptic pericaria in olfactory bulb of guinea pig, «Brain Res.», 63, 351-356.

Ramón-Moliner, E. (1975) - Can dendrites be presynaptic? In: «Advances in Neurology», Vol. 12, Ed. Kreutzberg Raven Press, N.Y..

Ralston, H. J. (1971) - Evidence for presynaptic dendrites and proposal for their mechanism of action, «Nature», 230, 585-587.

Reese, T. S. e Shepherd, G. M. (1972) - Dendro-dendritic synapses in the central nervous system. In: «Structure and function of Synapse», Ed. D. Pappas e D. P. Purpura. Raven N.Y..

Shepherd, G. M. (1970) - The olfactory bulb as a simple cortical system: experimental analysis and functional implications. In: «Neuroscience», Vol. II. The Rockefeller Univ. Press.

Shepherd, G. M. (1974) - The synaptic organization of the brain, Oxford Univ. Press.

Smith, C. A. e Sjostrand, F. S. (1961) - Structure of the nerve endings on the external hair cells of the guinea pig cochlea as studied by serial sections, «J. Ultrastruct. Res.», 5, 523-556.

Stefanelli, A., Cataldi, E. e Ieradi, L. A. (1976) - Sinapsi interneuroniche in aggregati di cellule cerebellari di embrione di pollo in coltura, «Rend. Acc. Naz. Lincei», ser. VIII, 591 831-834.

White, E. L. (1972) - Synaptic organization in the olfactory glomerulus of the mouse, «Brain Res.», 37, 69-80.

White, E. L. (1973) - Synaptic organization of the mammalian olfactory glomerulus: New finding including an intraspecific variation, «Brain Res.», 60, 299-313.