The developmental morphology of Torpedo marmorata: Electric lobe‐electromotoneuron proliferation and cell death
- 10 May 1982
- journal article
- research article
- Published by Wiley in Journal of Comparative Neurology
- Vol. 207 (2), 183-190
- https://doi.org/10.1002/cne.902070207
Abstract
Electromotoneuron proliferation and cell death have been quantitativelystudied in the electric lobe of Torpedo marmorata from an embryonic body‐length stage of 26‐mm to adult animals. These neurons project to the electric organ and form synapses with electrocytes which possess a remarkably large postsynaptic target surface. For this reason cell death would not be predicted to occur if synaptic competition were to be hypothesized as thecause. Isolated observations at the ultrastructural level suggested, however, that cell death was indeed taking place and therefore it seemed appropriate to examine this question in detail. Our findings show first that neuron production appears to be a continuous process throughout the period studied, generating totals of over 70,000 electromotoneurons per lobe by adulthood. Second, two waves of cell death were identified, one occurring early in embryogenesis (stage 30 mm), well before the onset of synaptogenesis, and a second coincident with the onset ofsynaptogenesis (stages 55‐74 mm). It is difficult to reconcile this latter wave with the hypothesis of synaptic competition as the postsynaptic surface at this time of development is largely devoid of synaptic contacts. We conclude that in the electromotor system of Torpedo, synaptic competition is probably not the mechanism of cell death.This publication has 18 references indexed in Scilit:
- Neuronal increase in various areas of the nervous system of the guppy, LebistesJournal of Comparative Neurology, 1980
- Aspects of the chemical embryology of the electromotor system of Torpedo marmorata with special reference to synaptogenesisNeuroscience, 1980
- Grafting of additional periphery reduces embryonic loss of neuronsBrain Research, 1979
- The developmental morphology of Torpedo marmorata: Electric organ—electrogenic phaseJournal of Comparative Neurology, 1979
- Neuronal death in the development of normal and hyperplastic spinal gangliaJournal of Experimental Zoology, 1978
- The developmental morphology of Torpedo marmorata: Electric organ — Myogenic phaseJournal of Comparative Neurology, 1978
- Developmental NeurobiologyPublished by Springer Nature ,1978
- Reduction of the naturally occurring motor neuron loss by enlargement of the peripheryJournal of Comparative Neurology, 1976
- CELL DEATHS IN NORMAL VERTEBRATE ONTOGENYBiological Reviews, 1951
- Proliferation, differentiation and degeneration in the spinal ganglia of the chick embryo under normal and experimental conditionsJournal of Experimental Zoology, 1949