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Receptor Reserves at α2-adrenergic and Dopaminergic Autoreceptors

  • M. Goldstein
  • E. Meller
  • C. H. Adler
Part of the Wenner-Gren Center International Symposium Series book series (WGCISS)

Abstract

Repeated observations that the maximal response elicited by an agonist can be obtained when only a fraction of receptors are occupied has led to the concept of “spare receptors” (or “receptor reserve”). A large pool of “spare receptors” has been found in many peripheral tissues and partial agonists with substantial, but submaximal, intrinsic efficacy often produce maximal response (Nickerson 1956; Stephenson 1956; Ariens et al., 1960). The law of mass action relates fractional occupancy to ligand concentration and it follows that a lower agonist concentration will suffice to elicit a particular level of response the greater the excess of functional receptors (larger receptor reserve). In order to delineate the relationship between receptor occupancy and closely coupled physiologic responses at α2-adrenergic and dopaminergic autoreceptors, we have inactivated a portion of these receptors with the recently described irreversible antagonist Nethoxycarbonyl-2-ethoxy-1, 2-dihydroquinoline (EEDQ) (Meller et al., 1985). This compound was found to dose-dependently inactivate central α2-adrenrgic and dopaminergic receptors in vivo.

Keywords

Dopamine Agonist Maximal Response Receptor Occupancy Receptor Binding Site Dopamine Receptor Agonist 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© The Wenner-Gren Center 1987

Authors and Affiliations

  • M. Goldstein
  • E. Meller
  • C. H. Adler

There are no affiliations available

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