Differential Actions of Neurotrophins in the Locus Coeruleus and Basal Forebrain

doi:10.1006/exnr.1993.1007

Experimental Neurology

Volume 119, Issue 1, January 1993, Pages 72-78

https://doi.org/10.1006/exnr.1993.1007 Get rights and content

Abstract

The neurotrophin gene family, including nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3), and NT-4/NT-5, supports the survival of distinct peripheral neurons, however, actions upon central neurons are relatively undefined. In this study we have compared different neurotrophins in the regulation of neuronal survival and function using dissociated embryonic cell cultures from two brain regions, the basal forebrain (BF) and locus coeruleus (LC). In the BF, NGF increased choline acetyl transferase (ChAT) activity, but did not influence cholinergic cell survival. In contrast to NGF, BDNF, NT-3, and the novel neurotrophin, NT-4, all increased ChAT activity and cholinergic cell survival. We also examined embryonic LC neurons in culture. LC neurons are unresponsive to NGF. In contrast, NT-3 and NT-4 elicited significant increases in survival of noradrenergic LC neurons, the first demonstration of trophic effects in this critical brain region. Identification of factors supporting coerulcal and basal forebrain neuronal survival may provide insight into mechanisms mediating degeneration of these disparate structures in clinical disorders.

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Regular ArticleDifferential Actions of Neurotrophins in the Locus Coeruleus and Basal Forebrain

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Regular Article
Differential Actions of Neurotrophins in the Locus Coeruleus and Basal Forebrain