Regulation of Dopamine Receptor Responsiveness by Glucocorticoids

  • J. E. Faunt
  • A. D. Crocker
Part of the Satellite Symposia of the IUPHAR 10th International Congress of Pharmacology book series (SSNIC)

Abstract

Identification of glucocorticoid (GC) specific binding sites in the brain (McEwen et al. 1969) stimulated inquiry into a possible modulatory role of GC’s on central neuronal activity. It has been established that the highest concentration of these sites are located in the hippocampus and therefore it has been a brain region more fully investigated than any other. However, since GC specific binding sites have also been identified in the caudate putamen (DeFiore and Turner 1983), and as this area is known to contain a high concentration of dopamine (DA) receptors, we sought to determine whether GC’s regulate DA receptor responsiveness in the striatum. The present study was therefore designed to investigate the effects of adrenalectomy (ADX) and subsequent chronic corticosterone replacement therapy on the behavioural effects of apomorphine and more specifically, to examine whether any changes observed were due to an altered responsiveness at the D1, D2 or both receptor subtypes. Finally, measurements of striatal D1 and D2 receptor concentration and affinity together with studies on DA-stimulated adenylate cyclase activity were carried out to determine possible neurochemical targets which may underlie the DA-mediated behavioural changes.

Keywords

Dopamine Glucocorticoid Haloperidol Corticosterone Apomorphine 

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References

  1. Cameron D.L. and Crocker A.D. (1986). A fixed interval momentary sampling method for assessing on-going behaviours induced by dopamine receptor agonists. Proc. 15th CINP Congress, 16.Google Scholar
  2. Defiore C.H. and Turner B.B. (1984). 3[H]corticosterone binding in caudate-putamen. Brain Research, 278: 93–101.CrossRefGoogle Scholar
  3. McEwen B.S., Weiss J.M. and Schwartz L.S. (1969). Uptake of corticosterone by rat brain and its concentration by certain limbic structures. Brain Research, 16: 227–241.CrossRefPubMedGoogle Scholar
  4. Molloy A. and Waddington J. (1984). Dopaminergic behaviour stereospecifically promoted by the D1 agonist R+SKF38393 and selectively blocked by the D1 antagonist SCH23390. Psychpharmacology, 73: 320–322.Google Scholar

Copyright information

© J.E. Faunt and A.D. Crocker 1988

Authors and Affiliations

  • J. E. Faunt
    • 1
  • A. D. Crocker
    • 1
  1. 1.Department of Clinical Pharmacology and Centre for NeuroscienceFlinders University of South AustraliaAustralia

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