Triiodothyronine exerts a trophic action on rat sensory neuron survival and neurite outgrowth through different pathways.

Détails

ID Serval
serval:BIB_297840B55061
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Institution
Titre
Triiodothyronine exerts a trophic action on rat sensory neuron survival and neurite outgrowth through different pathways.
Périodique
European Journal of Neuroscience
Auteur(s)
Walter I.B.
ISSN
0953-816X
Statut éditorial
Publié
Date de publication
1996
Peer-reviewed
Oui
Volume
8
Numéro
3
Pages
455-466
Langue
anglais
Résumé
Apart from several growth factors which play a crucial role in the survival and development of the central and peripheral nervous systems, thyroid hormones can affect different processes involved in the differentiation and maturation of neurons. The present study was initiated to determine whether triiodothyronine (T3) affects the survival and neurite outgrowth of primary sensory neurons in vitro. Dorsal root ganglia (DRG) from 19-day-old embryos or newborn rats were plated in explant or dissociated cell cultures. The effect of T3 on neuron survival was tested, either in mixed DRG cell cultures, where neurons grow with non-neuronal cells, or in neuron-enriched cultures where non-neuronal cells were eliminated at the outset. T3, in physiological concentrations, promoted the growth of neurons in mixed DRG cell cultures as well as in neuron-enriched cultures without added nerve growth factor (NGF). Since neuron survival in neuron-enriched cultures cannot be promoted by endogenous neurotrophic factors synthesized by non-neuronal cells, the increased number of surviving neurons was due to a direct trophic action of T3. Another trophic effect was revealed in this study: T3 sustained the neurite outgrowth of sensory neurons in DRG explants. The stimulatory effect of T3 on nerve fibre outgrowth was considerably reduced when non-neuronal cell proliferation was inhibited by the antimitotic agent cytosine arabinoside, and was completely suppressed when the great majority of non-neuronal cells were eliminated in neuron-enriched cultures. These results indicate that the stimulatory effect of T3 on neurite outgrowth is mediated through non-neuronal cells. It is conceivable that T3 up-regulates Schwann cell expression of a neurotrophic factor, which in turn stimulates axon growth of sensory neurons. Together, these results demonstrate that T3 promotes both survival and neurite outgrowth of primary sensory neurons in DRG cell cultures. The trophic actions of T3 on neuron survival and neurite outgrowth operate under two different pathways.
Mots-clé
Animals, Cell Survival, Cells, Cultured, Ganglia, Spinal, Immunohistochemistry, Neurites, Neurons, Rats, Rats, Wistar, Time Factors, Triiodothyronine
Pubmed
Web of science
Création de la notice
26/03/2009 12:09
Dernière modification de la notice
20/08/2019 14:09
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