Early and Late Effects of Steroid Hormones on the Central Nervous System

  1. Derek Chadwick Organizer and
  2. Kate Widdows
  1. B. Dubrovsky1,2,
  2. D. Filipini1,
  3. K. Gijsbers3 and
  4. M. K. Birmingham1

Published Online: 28 SEP 2007

DOI: 10.1002/9780470513989.ch14

Ciba Foundation Symposium 153 - Steroids and Neuronal Activity

Ciba Foundation Symposium 153 - Steroids and Neuronal Activity

How to Cite

Dubrovsky, B., Filipini, D., Gijsbers, K. and Birmingham, M. K. (2007) Early and Late Effects of Steroid Hormones on the Central Nervous System, in Ciba Foundation Symposium 153 - Steroids and Neuronal Activity (eds D. Chadwick and K. Widdows), John Wiley & Sons, Ltd., Chichester, UK. doi: 10.1002/9780470513989.ch14

Author Information

  1. 1

    Laboratories of Neurophysiology and Steroid Biochemistry, McGill University, 1033 Pine Avenue West, Montreal, Quebec, Canada H3A 1A1

  2. 2

    Department of Psychiatry, Neurophysiology Laboratory, McGill University, 1033 Pine Avenue West, Montreal, Quebec, Canada H3A 1Al

  3. 3

    Psychology Department, Stirling University, Stirling, FK9 4LA, UK

Publication History

  1. Published Online: 28 SEP 2007

ISBN Information

Print ISBN: 9780471926894

Online ISBN: 9780470513989

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Keywords:

  • steroid hormones;
  • central nervous system;
  • depolarization;
  • 18-hydroxydeoxycorticosterone 21-acetate;
  • lipid solubility

Summary

Steroids have fast and probably partly GABA-mediated central anaesthetic effects for which a strict structure-function correlation is required. They also affect short- and long-term activity in the CNS in other ways. One of these is long-term potentiation (the persistent facilitation of synaptic transmission), which occurs particularly in the hippocampus after repetitive stimulation of a fibre pathway. Two clearly distinguished components of the evoked response can be studied in the hippocampus: the excitatory postsynaptic potential (EPSP) which denotes the graded depolarization of the somadendritic region of the neuron and the population spike (PS), a manifestation of the all-or-none discharge of the cell action potential. Corticosterone had a significant depressant effect on the EPSP component of the evoked response immediately and 15 min after injection. Thereafter EPSP amplitudes were within normal values. Corticosterone significantly decreased the PS immediately after the train, the component remaining low 30 min after the train. 5α-Dihydrocorticosterone (a ring A-reduced metabolite of corticosterone) significantly reduced the PS component of the response at all times after injection. 18-Hydroxydeoxycorticosterone and deoxycorticosterone significantly decreased both EPSP and PS components of the evoked response from the time of infusion. Contrary to expectation, tetrahydrodeoxycorticosterone was ineffective in decreasing, and if anything, enhanced the development of long-term potentiation. 18-Hydroxydeoxycorticosterone 21-acetate behaved like vehicle, except for the first 30 min after injection, when the EPSP was decreased. Different steroids can selectively affect different parts of a neuron and appear to show a different structure-function correlation for long-term potentiation from that required for anaesthesia.