Muscle Activity and Motor Neuron Death in the Spinal Cord of the Chick Embryo

  1. Gregory Bock Organizer and
  2. Maeve O'Connor
  1. Ronald W. Oppenheim

Published Online: 28 SEP 2007

DOI: 10.1002/9780470513422.ch7

Ciba Foundation Symposium 126 - Selective Neuronal Death

Ciba Foundation Symposium 126 - Selective Neuronal Death

How to Cite

Oppenheim, R. W. (2007) Muscle Activity and Motor Neuron Death in the Spinal Cord of the Chick Embryo, in Ciba Foundation Symposium 126 - Selective Neuronal Death (eds G. Bock and M. O'Connor), John Wiley & Sons, Ltd., Chichester, UK. doi: 10.1002/9780470513422.ch7

Author Information

  1. Department of Anatomy, Bowman Gray School of Medicine, Wake Forest University, 300 South Hawthorne Road, Winston-Salem, NC 27103, USA

Publication History

  1. Published Online: 28 SEP 2007

ISBN Information

Print ISBN: 9780471910923

Online ISBN: 9780470513422

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Keywords:

  • muscle activity;
  • motor neuron death;
  • spinal cord;
  • chick embryo;
  • pharmacological blockade

Summary

During embryonic development in vertebrates about half the spinal motor neurons degenerate naturally after an initial period of normal differentiation. Motor neuron survival during this period is regulated by influences associated with both afferent and target contacts. Target-associated influences are regulated, at least in part, by activity (i.e. neuromuscular transmission or muscle contraction). Pharmacological blockade of neuromuscular activity reduces or prevents normal cell death whereas induced hyperactivity of targets enhances the death of motor neurons. Information supporting these assertions is reviewed and evidence is presented from studies which attempt to elucidate the major site at which neuromuscular activity affects motor neuron survival and degeneration in the chick embryo. Finally, a model and some supporting evidence are described in which activity is thought to regulate the production or availability of a target-derived trophic factor required by motor neurons for their survival during certain critical phases of early development.