Spontaneous and evoked activity of fetal primary afferents in vivo (original) (raw)

Nature volume 326, pages 603–605 (1987)Cite this article

Abstract

The first movements of the fetus are apparently random and spontaneous1,2. Their onset coincides with the growth of dorsal root afferents into the spinal cord3,4 and it is possible that they are not simply a result of spontaneous motoneuron activity but are reflex responses to sensory stimulation5. It is not clear what stimuli could normally evoke such reflexes because nothing is known of the properties of primary afferent neurons in the fetus. I have investigated this by making recordings from single dorsal root ganglion cells in fetal rats in vivo. The afferents have small, defined receptive fields and respond to mechanical stimulation of skin or muscle at intensities that might occur in utero. Many of them are also chemosensitive. Unlike postnatal afferents they display background activity which peaks at the same age as fetal movements. Repeated stimulation causes long-lasting increases of both background and evoked activity. Such sensory input is likely to have a considerable influence on fetal movements and on the development of spinal cord connections.

This is a preview of subscription content, access via your institution

Access options

Subscribe to this journal

Receive 51 print issues and online access

$199.00 per year

only $3.90 per issue

Buy this article

Prices may be subject to local taxes which are calculated during checkout

Additional access options:

Similar content being viewed by others

References

  1. Angulo y Gonzalez, A. W. J. comp. Neurol 55, 395–442 (1932).
    Article Google Scholar
  2. Narayanan, C. H., Fox, M. W. & Hamburger, V. Behaviour 40, 100–134 (1971).
    Article CAS Google Scholar
  3. Altman, J. & Bayer, S. A. The Development of the Rat Spinal Cord (Springer, Berlin, 1984).
    Book Google Scholar
  4. Smith, C. L. J. comp. Neurol 220, 29–43 (1983).
    Article ADS CAS Google Scholar
  5. Windle, W. F. The Physiology of the Foetus (Phildalephia, 1940).
    Google Scholar
  6. Fitzgerald, M. J. Physiol, Lond. 383, 79–92 (1987).
    Article CAS Google Scholar
  7. Lynn, B. & Carpenter, S. E. Brain Res. 238, 29–43 (1982).
    Article CAS Google Scholar
  8. Diamond, J. & Nurse, C. A. Neuroscience 11, 509–520 (1984).
    Article Google Scholar
  9. Zelena, J. J. Embryol. exp. Morph. 5, 283–289 (1957).
    Google Scholar
  10. Bradley, R. M. & Mistretta, C. M. Physiol Rev. 55 352–382 (1975).
    Article CAS Google Scholar
  11. Fulton, B. P. Neurosci. Lett. 73, 125–130 (1987).
    Article CAS Google Scholar

Download references

Author information

Authors and Affiliations

  1. Department of Anatomy and Embryology, University College London, Gower Street, London, WC1 6BT, UK
    Maria Fitzgerald

Authors

  1. Maria Fitzgerald
    You can also search for this author inPubMed Google Scholar

Rights and permissions

About this article

Cite this article

Fitzgerald, M. Spontaneous and evoked activity of fetal primary afferents in vivo.Nature 326, 603–605 (1987). https://doi.org/10.1038/326603a0

Download citation

This article is cited by