NGF induces neonatal rat sensory neurons to extend dendrites in culture after removal of satellite cells.

TitleNGF induces neonatal rat sensory neurons to extend dendrites in culture after removal of satellite cells.
Publication TypeJournal Article
Year of Publication1993
AuthorsDe Koninck P, Carbonetto S, Cooper E
JournalJ Neurosci
Volume13
Issue2
Pagination577-85
Date Published1993 Feb
ISSN0270-6474
KeywordsAnimals, Animals, Newborn, Axons, Cells, Cultured, Dendrites, Immunohistochemistry, Isoquinolines, Microtubule-Associated Proteins, Nerve Growth Factors, Neurons, Afferent, Nodose Ganglion, Rats, Receptors, Cholinergic
Abstract

Vertebrate sensory neurons have a pseudo-unipolar morphology; their somata are covered by satellite cells and lack dendrites or synaptic contacts. However, when neonatal rat sensory neurons from the nodose ganglia develop in culture in absence of satellite cells and with NGF, they form synapses among themselves. In this study, we investigated whether neonatal rat nodose neurons express dendrites under the same culture conditions. We show by Lucifer yellow injection that nodose neurons remain typically unipolar when cocultured with their ganglionic satellite cells. However, when these neurons are cultured without satellite cells, virtually all neurons acquire a multipolar morphology. Moreover, when NGF is added to satellite cell-free cultures, several neurons extend dendrites; these processes stain positively for microtubule-associated protein-2. NGF induces a 17-fold increase in dendritic outgrowth after 3 weeks but has little effect on axon number. In addition, we find that the ability of nodose neurons to extend dendrites is developmentally regulated. Furthermore, in a combined morphological and electrophysiological study, using whole-cell voltage-clamp technique with Lucifer yellow in the recording solution, we demonstrate a positive correlation between the extent of dendritic outgrowth and the density of ACh currents, suggesting that these dendrites have ACh receptors. Our results indicate that neonatal rat nodose neurons are capable of extending dendrites and that extrinsic factors can induce or suppress their extension. In addition, the results suggest that these dendrites may act as principal post-synaptic structures for synapse formation that occurs in these cultures.

Alternate JournalJ. Neurosci.
PubMed ID8426228

Funding

Our research endeavors are made possible by the following agencies:

Canadian Institutes of Health Research - Instituts de recherche en santé du Canada Fonds de recherche du Québec – Nature et technologies (FRQNT)Fonds de la recherche en santé du Québec NARSAD Natural Sciences and Engineering Research Council of Canada (NSERC) - Conseil de recherche en sciences naturelles et en génie du Canada (CRSNG)innovation.caHuman Frontier Science Program