Skip to main content
Log in

Large dense-core vesicle exocytosis and membrane recycling in the mossy fibre synapses of the rabbit hippocampus during epileptiform seizures

  • Published:
Journal of Neurocytology

Summary

The ultrastructure of the hippocampal mossy fibre layer was studied in ultrathin sections and freeze-fracture preparations of rabbits under deep Nembutal anaesthesia, after recovery from ether anaesthesia, and 40 min after a single injection of methoxypyridoxine, that is, during the second generalized seizure discharge. The giant mossy fibre boutons contain two types of vesicles: evenly distributed, small round clear vesicles (50 nm) and a few scattered large dense-core vesicles (100 nm). In rare instances fusion of dense-core vesicles with the presynaptic membrane was observed. No differences in the morphology of the mossy fibre synapses were found between anaesthetized and unanaesthetized animals. During epileptiform seizures, however, the size and shape of clear and dense-core vesicles varied greatly. The active synaptic zones were covered with large, core-containing omega profiles or bumps and indentations. Only dense-core vesicles seem to undergo exocytosis. A fusion of clear vesicles with the presynaptic membrane was not observed.

Various explanations for the fact that only dense-core vesicles seem to undergo exocytosis are discussed. The hypothesis is put forward that in the mossy fibre bouton two morphologically and functionally distinct populations of synaptic vesicles exist and that only one of them undergoes visible irreversible exocytosis, whereas the majority, that is, the small vesicles discharge their transmitter by reversible fusion.

After MP injection features of membrane retrieval were also prominent. Frequently, at the borders of the active synaptic zones coated membrane convolutes of both pre- and postsynaptic membranes had invaded the terminals as well as the postsynaptic spine. Thus, in contrast to electrical stimulation, the self-sustained seizures allow energy-expensive processes such as extensive membrane internalization to take place during the interictal pauses.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  • Akert, K., Streit, P., Sandri, C., Livingston, R. &Moor, H. (1972) Synapsen im Zeichen erhöhter und erniedrigter Aktivität.Schweizer Archiv für Neurologie, Neurochirurgie und Psychiatrie 111, 227–36.

    Google Scholar 

  • Andres, K. H. (1964) Mikropinocytose im Zentralnervensystem.Zeitschrift für Zellforschung und mikroskopische Anatomie 64, 63–73.

    Google Scholar 

  • Basbaum, C. B. &Heuser, J. E. (1979) Morphological studies of stimulated adrenergic axon varicosities in the mouse vas deferens.Journal of Cell Biology 80, 310–25.

    Google Scholar 

  • Blackstad, T. W. &Kjaerheim, Å. (1961) Special axodendritic synapses in the hippocampal cortex. Electron and light microscopic studies on the layer of mossy fibres.Journal of Comparative Neurology 117, 133–59.

    PubMed  Google Scholar 

  • Branton, D., Bullivant, S., Gilula, N. B., Karnovsky, M. J., Moor, H., Mühlethaler, K., Northcote, D. H., Packer, L., Satir, D., Satir, P., Speth, V., Staehlin, L. A., Steere, R. L. &Weinstein, R. S. (1975) Freeze-etching nomenclature.Science 190, 54–6.

    PubMed  Google Scholar 

  • Ceccarelli, R., Hurlburt, W. P. &Mauro, A. (1972) Depletion of vesicles from frog neuromuscular junctions by prolonged tetanic stimulation.Journal of Cell Biology 54, 30–8.

    PubMed  Google Scholar 

  • Crawford, I. L. &Connor, J. D. (1973) Localization and release of glutamic acid in relation to the hippocampal mossy fiber pathway.Nature 244, 442–3.

    PubMed  Google Scholar 

  • Del Castillo, J. &Katz, B. (1954) Quantal components of the end plate potential.Journal of Physiology 124, 560–73.

    PubMed  Google Scholar 

  • Devreotes, P. N. &Fambrough, D. M. (1975) Acetylcholine receptor turnover in membranes of developing muscle fibers.Journal of Cell Biology 65, 353–8.

    Google Scholar 

  • Eckenhoff, M. F. &Pysh, J. J. (1979) Double-walled coated vesicle formation: evidence for massive and transient conjugate internalization of plasma membranes during cerebellar development.Journal of Neurocytology 8, 623–38.

    PubMed  Google Scholar 

  • Fatt, P. &Katz, B. (1952) Spontaneous subthreshold activity at motor nerve endings.Journal of Physiology 117, 109–28.

    PubMed  Google Scholar 

  • Gray, E. G. &Willis, R. A. (1970) On synaptic vesicles, complex vesicles and dense projections.Brain Research 24, 149–68.

    PubMed  Google Scholar 

  • Hamlyn, L. M. (1962) The fine structure of the mossy fibre endings in the hippocampus of the rabbit.Journal of Anatomy 96, 112–20.

    PubMed  Google Scholar 

  • Hassler, C., Hassler, R., Okada, Y. &Bak, I. J. (1971) Pre-ictal and ictal changes of serotonin, GABA and glutamate contents in different regions of rabbit brain during methoxypyridoxine-induced seizures.Acta neurologica latinoamericana 17, 595–611.

    PubMed  Google Scholar 

  • Heuser, J. E. &Reese, T. S. (1973) Evidence for recycling of synaptic vesicle membrane during transmitter release at frog neuromuscular junction.Journal of Cell Biology 57, 315–44.

    PubMed  Google Scholar 

  • Heuser, J. E., Reese, T. S., Dennis, M. J., Jan, Y., Jan, L. &Evans, L. (1979) Synaptic vesicle exocytosis by quick freezing and correlated with quantal transmitter release.Journal of Cell Biology 81, 275–300.

    PubMed  Google Scholar 

  • Hökfelt, T., Ljungdahl, A., Steinbusch, H., Verhofstad, A., Nilsson, G., Brodin, E., Pernow, B. &Goldstein, M. (1978) Immunohistochemical evidence of substance P-like immunoreactivity in some 5-hydroxytryptamine-containing neurons in the rat central nervous system.Neuroscience 3, 517–38.

    PubMed  Google Scholar 

  • Holtzman, E. (1977) The origin and fate of secretory packages, especially synaptic vesicles.Neuroscience 2, 327–55.

    PubMed  Google Scholar 

  • Hubbard, J. J. &Kwanbunbumpen, S. (1968) Evidence for the vesicle hypothesis.Journal of Physiology 194, 407–20.

    PubMed  Google Scholar 

  • Jones, S. F. &Kwanbunbumpen, S. (1970) The effects of nerve stimulation and hemicholinium on synaptic vesicles at the mammalian neuromuscular junction.Journal of Physiology 207, 31–50.

    PubMed  Google Scholar 

  • Kadota, K. &Kadota, T. (1978) Detection of depolarization-induced coated vesicles within presynaptic terminals in cat sympathetic ganglia maintained under a low temperature.Brain Research 151, 201–5.

    PubMed  Google Scholar 

  • Korneliussen, H. (1972) Ultrastructure of normal and stimulated motor endplates.Zeitschrift für Zellforschung und mikroskopische Anatomie 130, 28–57.

    Google Scholar 

  • Landis, D. M. D. &Reese, T. S. (1974) Differences in membrane structure between excitatory and inhibitory synapses in the cerebellar cortex.Journal of Comparative Neurology 155, 93–126.

    PubMed  Google Scholar 

  • Lorente De No, R. (1934) Studies on the structure of the cerebral cortex. II. Continuation of the study of the ammonic system.Journal für Psychologie und Neurologie (Leipzig) 46, 113–77.

    Google Scholar 

  • Model, P. G., Highstein, S. M. &Bennett, M. V. L. (1975) Depletion of vesicles and fatigue of transmission at a vertebrate central synapse.Brain Research 98, 209–28.

    PubMed  Google Scholar 

  • Moor, H. &Mühlethaler, K. (1963) Fine structure of frozen-etched yeast cells.Journal of Cell Biology 17, 608–28.

    Google Scholar 

  • Nitsch, C. (1976) Antivitamin B6-induced ultrastructural changes in the hippocampus of the convulsant rabbit and its biochemical correlates.Acta neurochirurgica 23, 101–9.

    PubMed  Google Scholar 

  • Nitsch, C. (1978) Role of hippocampus in convulsions caused by a critical GABA-decrease. InAdvances in Epileptology (edited byMeinardi, H. andRowan, A. J.), pp. 151–155. Amsterdam: Swets & Zeitlinger.

    Google Scholar 

  • Nitsch, C. (1980) Regulation of GABA metabolism in discrete rabbit brain regions under methoxypyridoxine. Regional differences in cofactor saturation and the preictal activation of glutamate decarboxylase activity.Journal of Neurochemistry 34, 822–30.

    Google Scholar 

  • Nitsch, C. &Bak, I. J. (1974) Die Mossfaserendigungen des Ammonshorn, dargestellt in der Gefrierätztechnik.Verhandlungen der Anatomischen Gesellschaft 68, 319–23.

    PubMed  Google Scholar 

  • Nitsch, C. &Okada, Y. (1976) Differential decrease of GABA in the substantia nigra and other discrete regions of the rabbit brain during the preictal period of methoxypyridoxine-induced seizures.Brain Research 105, 173–8.

    PubMed  Google Scholar 

  • Nitsch, C. &Okada, Y. (1979) Distribution of glutamate in layers of the rabbit hippocampal fields CA1, CA3, and the dentate area.Journal of Neuroscience Research 4, 161–7.

    PubMed  Google Scholar 

  • Pfenninger, K., Akert, K., Moor, H. &Sandri, C. (1972) The fine structure of freeze-fractured presynaptic membranes.Journal of Neurocytology 1, 129–49.

    PubMed  Google Scholar 

  • Pickel, V. M., Joh, T. H., Reis, D. J., Leeman, S. E. &Miller, R. J. (1979) Electron microscopic localization of substance P and enkephalin in axon terminals related to dendrites of catecholaminergic neurons.Brain Research 160, 387–400.

    PubMed  Google Scholar 

  • Purpura, D. P., Berl, S., Gonzales-Monteagudo, O. &Wyatt, A. (1960) Brain amino acid changes during methoxypyridoxine-induced seizures (cat). InInhibition in the Nervous System and GABA (edited byRoberts, E.), pp. 331–335. Oxford, New York: Pergamon.

    Google Scholar 

  • Purpura, D. P. &Gonzales-Monteagudo, O. (1960) Acute effects of methoxypyridoxine on hippocampal end-blade neurons: an experimental study of ‘special pathoclisis’ in the cerebral cortex.Journal of Neuropathology and Experimental Neurology 19, 421–32.

    PubMed  Google Scholar 

  • Pysh, J. J. &Wiley, R. G. (1974) Synaptic vesicle depletion and recovery in cat sympathetic ganglia electrically stimulatedin vivo.Journal of Cell Biology 60, 365–74.

    PubMed  Google Scholar 

  • Rose, S. J., Pappas, G. D. &Kriebel, M. E. (1978) The fine structure of identified frog neuromuscular junctions in relation to synaptic activity.Brain Research 144, 213–39.

    PubMed  Google Scholar 

  • Sandri, C., Akert, K., Livingston, E. B. &Moor, H. (1972) Particle aggregations at specialized sites in freeze-etched postsynaptic membranes.Brain Research 41, 1–16.

    PubMed  Google Scholar 

  • Smith, B. H. &Kreutzberg, G. W. (editors) (1976) Neuron-target cell interactions.Neurosciences Research Program Bulletin 14, (3).

  • Sotelo, C. &Palay, S. (1968) The fine structure of the lateral vestibular nucleus in the rat. I. Neurons and neuroglial cells.Journal of Cell Biology 36, 151–79.

    Google Scholar 

  • Stephan, H. (1975)Allocortex Part 9 of Vol. 4Nervensystem ofHandbuch der mikroskopischen Anatomie des Menschen. Berlin, Heidelberg, New York: Springer-Verlag.

    Google Scholar 

  • Storm-Mathisen, J. &Iversen, L. L. (1979) Uptake of3H-glutamic acid in excitatory nerve endings: light and electronmicroscopic observations in the hippocampal formation of the rat.Neuroscience 4, 1237–53.

    PubMed  Google Scholar 

  • Streit, P., Akert, K., Sandri, C., Livinston, R. B. &Moor, H. (1972) Dynamic ultrastructure of presynaptic membranes at nerve terminals in the spinal cord of rats. Anesthetized and unanesthetized preparations compared.Brain Research 48, 11–26.

    PubMed  Google Scholar 

  • Venzin, M., Sandri, C., Akert, K. &Wyss, U. R. (1977) Membrane associated particles of the presynaptic active zone in rat spinal cord. A morphometric analysis.Brain Research 130, 393–404.

    Google Scholar 

  • Westrum, L. E. &Blackstad, T. W. (1962) An electron microscopic study of the stratum radiatum of the rat hippocampus with particular emphasis on synaptology.Journal of Comparative Neurology 19, 281–309.

    Google Scholar 

  • Zimmermann, H. &Denston, C. R. (1977) Recycling of synaptic vesicles in the cholinergic synapses of theTorpedo electric organ during induced transmitter release.Neuroscience 2, 695–714.

    PubMed  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and permissions

About this article

Cite this article

Nitsch, C., Rinne, U. Large dense-core vesicle exocytosis and membrane recycling in the mossy fibre synapses of the rabbit hippocampus during epileptiform seizures. J Neurocytol 10, 201–219 (1981). https://doi.org/10.1007/BF01257967

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF01257967

Keywords

Navigation