Receptor Reserves at α2-adrenergic and Dopaminergic Autoreceptors

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