Full agonists, partial agonists and inverse agonists

An agonist is a ligand that binds to a receptor and alters the receptor state resulting in a biological response. A full agonist reaches the maximal response capability of the system, and a partial agonist does not (even at full receptor occupancy). A partial agonist acts as an antagonist in the presence of a full agonist (if they compete for the same receptors). An inverse agonist is a ligand that by binding to receptors reduces the fraction of them in an active conformation. Spare receptors are said to exist wherever a full agonist can cause a maximum response when occupying only a fraction of the total receptor population.

GraphPad Prism 10 Curve Fitting Guide - Equation: Operational model - Partial agonist

Intrinsic activity - Wikipedia

Pharmacodynamics Basicmedical Key

Effects of UTP, CTP, GTP, and ATP on ternary complex formation in Sf9

Molecular Mechanisms of Drug Actions: From Receptors to Effectors

Emerging concepts of G protein-coupled receptor (GPCR) function and drug discovery - Drug Discovery World (DDW)

1 Pharmaceutical definitions of different ligand types: full agonists

Drug–Receptor Interaction

Potency and efficacy

Effects of UTP, CTP, and GTP on AC activity in Sf9 membranes expressing

Emerging concepts of G protein-coupled receptor (GPCR) function and drug discovery - Drug Discovery World (DDW)