Fine structural studies of synaptogenesis in the superficial layers of the chick optic tectum
- 1 February 1980
- journal article
- research article
- Published by Springer Nature in Journal of Neurocytology
- Vol. 9 (1), 79-93
- https://doi.org/10.1007/bf01205228
Abstract
Synaptogenesis in the superficial layers of the rostral pole of the optic tectum has been studied in the chick from embryonic day six (E6) to seven days post-hatching. Symmetrical membrane densities orpuncta adhaerentia are observed prior to the detection of synapses and throughout development. Immature synaptic contacts are observed by E7. These early synapses are primarily axodendritic; however, somatodendritic, dendrodendritic, axosomatic and axoglial synapses are also observed. The majority of these synapses have asymmetrical membrane densities and the presynaptic terminals contain clear, spherical, synaptic vesicles. Synaptic terminals containing pleomorphic vesicles and making symmetrical synaptic contacts are not commonly observed until the third week of embryonic development, and may represent the onset of inhibitory function within the tectum. Comparison of the number of synapses per unit area in control versus experimental tecta, after unilateral eye enucleations at E3, indicates that the presynaptic terminals of some synapses present at E8 are of retinal origin. It is suggested that the development of retinotectal synapses follows a rostrocaudal gradient in the tectum and corresponds to the intrinsic tectal pattern of cytoarchitectonic differentiation.This publication has 39 references indexed in Scilit:
- Studies on the development of the chick optic tectum. IV. An autoradiographic study of the development of retino-tectal connectionsBrain Research, 1975
- The development of synapses in the cerebellar cortex of the chick embryoJournal of Neurocytology, 1974
- Quantitative analysis of the synaptogenic period in the trigeminal mesencephalic nucleusThe Anatomical Record, 1973
- Synaptic junctions in the developing chick optic tectumCellular and Molecular Life Sciences, 1973
- Synaptic junction development in the spinal cord of an amphibian embryo: An electron microscope studyCell and tissue research, 1973
- Coated vesicles and synaptogenesis. A developmental study in the cerebellar cortex of the ratBrain Research, 1971
- Studies on the developing cerebellums. Ultrastructure of the growth conesJournal of Comparative Neurology, 1968
- Development of fine structure of spinal cord in monkey fetuses. II. Pre‐reflex period to period of long intersegmental reflexesJournal of Comparative Neurology, 1968
- An electron-microscopic study of the early outgrowth from chick spinal cord in vitroCell and tissue research, 1968
- Development of the retinotectal topographic projection in the chick embryoExperimental Neurology, 1965