Neurotrophic factors

doi:10.1017/CBO9780511544873.009

8 - Neurotrophic factors

from Part I - Basic aspects of neurodegeneration

Published online by Cambridge University Press: 04 August 2010

Anthony E. Lang and

M. Flint Beal: Affiliation:
Cornell University, New York
Anthony E. Lang: Affiliation:
University of Toronto
Albert C. Ludolph: Affiliation:
Universität Ulm, Germany
Michael Sendtner: Affiliation:
Institute for Clinical Neurobiology, Würzburg, Germany

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Summary

Introduction

During development of higher vertebrates, many types of neurons including spinal and bulbar motoneurons are generated in excess. When developing motoneurons become postmitotic, they grow out axons and make contact with their target tissue, the skeletal muscle. Subsequently, about 50% of the motoneurons are lost during a critical process, which is called physiological motoneuron cell death. This phenomenon has been the focus of research for about a century and has led to the identification of neurotrophic factors that regulate survival of motoneurons during this developmental period. Motoneuron cell death is also observed in vitro when these neurons are isolated from the embryonic avian or rodent spinal cord. These cultured motoneurons have been a useful tool for studying basic mechanisms underlying neuronal degeneration. Such studies have revealed insights into signaling pathways that modulate survival during development and that might be disturbed under pathophysiological conditions in neurodegenerative disorders such as amyotrophic lateral sclerosis (ALS). However, specific differences in mechanisms that regulate survival of developing and postnatal motoneurons have also been identified. These findings could help to develop new therapeutic strategies that could counteract the pathophysiological processes underlying ALS.

Developmental motoneuron cell death

Viktor Hamburger and other pioneer researchers have shown during the first part of the twentieth century that the developmental cell death of motoneurons is guided by influences provided from the target tissue (Hamburger, 1934, 1958).

Type: Chapter
Information: Neurodegenerative Diseases
Neurobiology, Pathogenesis and Therapeutics
, pp. 94 - 107

DOI: https://doi.org/10.1017/CBO9780511544873.009 [Opens in a new window]

Publisher: Cambridge University Press

Print publication year: 2005

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