Summary
Synaptogenesis was studied in 3, 4, 5 and 8 day embryos. A small number of synapses were located in the marginal zone near the motor region in 3–4 day embryos. At 5 days the number of synapses increased and synapses were also found within the motor region. At 8 days there was a large increase in the total number of synapses and most were found within the motor region. At this stage, for the first time, many knobs contained flattened synaptic vesicles. Synapses on the perikarya were rarely but occasionally observed both at the 5 and 8 day stages. A few synapses were located in the marginal zone near dorsal root entry at the 5 day stage and the number increased by the 8 day stage. Although this sequence of synaptic development resembles that found in the monkey fetus, differences in behavioral development between these two species indicate that descriptive relationships between synaptic and behavioral development must be made cautiously. Furthermore, evidence is presented which indicates that the junctional specialization is the first sign of a developing synapse and that coated vesicles, possibly derived from the Golgi apparatus, which are fused to the neural plasmalemma may be related to the initial formation of the junctional specialization.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Adinolfi, A. M.: Morphogenesis of synaptic junctions in layers I and II of the somatic sensory cortex. Exp. Neurol.34, 372–382 (1972).
Altman, J.: Coated vesicles and synaptogenesis. A developmental study in the cerebellar cortex of the rat. Brain Res.30, 311–322 (1971).
Bodian, D.: Development of fine structure of spinal cord in monkey fetuses II. Pre-reflex to period of long intersegmental reflexes. J. comp. Neurol.133, 113–166 (1968).
Brinkman, R., Martin, A. H.: A cytoarchitectonic and radioautographic study of the avian spinal cord. Anat. Rec.166, 282 (1970).
Bunge, M. B., Bunge, R. P., Peterson, E. R.: The onset of synapse formation in spinal cord cultures as studied by electron microscopy. Brain Res.6, 728–749 (1967).
Cajal, S. Ramon y: Studies on vertebrate neurogenesis. Trans. by L. Guth. Springfield: Thomas 1960.
Friend, D. S., Farquhar, M. G.: Functions of coated vesicles during protein absorption in the rat vas deferens. J. Cell Biol.35, 357–376 (1967).
Glees, P., Sheppard, B. L.: Electron microscopical studies of the synapse in the developing chick spinal cord. Z. Zellforsch.62, 356–362 (1964).
Hamburger, V., Balaban, M.: Observations and experiments on spontaneous rhythmical behavior in the chick embryo. Develop. Biol.7, 533–545 (1963).
Hamburger, V., Hamilton, H. L.: A series of normal stages in the development of the chick embryo. J. Morphol.88, 49–92 (1951).
Holtzman, E., Novikoff, A. B., Villaverde, H.: Lysosomes and GERL in normal and chromatolytic neurons of the rat ganglion nodosum. J. Cell Biol.33, 419–435 (1967).
Larramendi, L. M. H.: Analysis of synaptogenesis in the mouse. In: R. Llinas (ed.), Neurobiology of cerebellar evolution and development, p. 803–845. Chicago: Am. Med. Assn. Educ. & Res. Fdn. 1969.
Lund, R. D., Lund, J. S.: Development of synaptic patterns in the superior colliculus of the rat. Brain Res.42, 1–20 (1972).
Maul, G. G., Brumbaugh, J. A.: On the possible function of coated vesicles in melanogenesis of the regenerating fowl feather. J. Cell Biol.48, 41–48 (1971).
Narayanan, C. H., Fox, M. W., Hamburger, V.: Prenatal development of spontaneous and evoked activity in the rat (Rattus norvegicus albinus). Behavior40, 100–135 (1971).
Oppenheim, R. W., Foelix, R. F.: Synaptogenesis in the chick embryo spinal cord. Nature (Lond.)235, 126–128 (1972).
Orr, D. W., Windle, W. F.: The development of behavior in chick embryos: the appearance of somatic movements. J. comp. Neurol.60, 271–285 (1934).
Purpura, D. P., Shofer, R. J., Housepian, E. M., Noback, C. R.: Comparative ontogenesis of structure-function relations in cerebral and cerebellar cortex. Prog. in Brain Res.14, 99–115 (1964).
Rosenbluth, J., Wissig, S. L.: The distribution of exogenous ferritin in toad spinal ganglia and the mechanism of its uptake by neurons. J. Cell Biol.23, 307–325 (1964).
Roth, T. F., Porter, K. R.: Yolk protein uptake in the oocyte of the mosquitoAedes aegypti. L. J. Cell Biol.20, 313–331 (1964).
Sperry, R. W.: Chemoaffinity in the orderly growth of nerve fiber patterns and connections. Proc. nat. Acad. Sci. (Wash.)50, 703–710 (1963).
Stelzner, D. J.: The developmental relationships of coated and synaptic vesicles to the Golgi apparatus and smooth ER. Anat. Rec.169, 437 (1971a).
Stelzner, D. J.: The relationship between synaptic vesicles, Golgi apparatus, and smooth endoplasmic reticulum; a developmental study using the zinc iodide-osmiun technique. Z. Zellforsch.120, 332–345 (1971b).
Stelzner, D. J.: Early stages of synaptogenesis in the cervical spinal cord of the chick embryo. Anat. Rec.172, 412 (1972).
Waxman, S. G., Pappas, G. D.: Pinocytosis at postsynaptic membranes: electron microscopic evidence. Brain Res.14, 240–244 (1969).
Wechsler, W.: Elektronenmikroskopischer Beitrag zur Nervenzelldifferenzierung und Histogenese der grauen Substanz des Rückenmarks von Hühnerembryonen. Z. Zellforsch.74, 401–422 (1966).
Author information
Authors and Affiliations
Additional information
We would like to thank Dr. R. W. Guillery for his advice and criticism on the research and preparation of this manuscript and Drs. C.A. Benzo and J.A. Horel for their critical appraisal of its content. We would also like to thank Mrs. Judy Strauss for her valuable photographic assistance. Supported by Grants 5 T01 GM00723, NS06662, NS09251, NS10579, Institutional Grant 118426A, and SUNY Res. Foundation Grant 011-7119A.
Rights and permissions
About this article
Cite this article
Stelzner, D.J., Martin, A.H. & Scott, G.L. Early stages of synaptogenesis in the cervical spinal cord of the chick embryo. Z.Zellforsch 138, 475–488 (1973). https://doi.org/10.1007/BF00572291
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00572291