ABSTRACT
Receptors ....................................................................................................................25 1.4.4 The del Castillo-Katz Mechanism: The Relationship between Agonist
Concentration and the Fraction of Receptors in an Active Form ...............................26 1.4.5 The del Castillo-Katz Mechanism: The Interpretation of Efcacy
for Ligand-Gated Ion Channels ..................................................................................28 1.4.6 The Interpretation of Efcacy for Receptors Acting through G-Proteins ..................30 1.4.7 Constitutively Active Receptors, Inverse Agonists ..................................................... 31 1.4.8 Attempting to Estimate the Efcacy of a Partial Agonist from the End
Response of a Complex Tissue ...................................................................................34 1.5 Inhibitory Actions at Receptors: Surmountable Antagonism ................................................. 39
1.5.1 Overview of Drug Antagonism .................................................................................. 39 1.5.1.1 Mechanisms Not Involving the Receptor Macromolecule through
Which the Agonist Acts ............................................................................... 39 1.5.1.2 Mechanisms Involving the Receptor Macromolecule .................................40
