Abstract
The hyperbolic parabola is commonly used to summarize kinetics for enzyme reactions and receptor binding kinetics. Depending on the experimental conditions, certain assumptions are valid but others might be violated so that the parameters used to fit this hyperbolic function, the maximum asymptote and the equilibrium constant, require different interpretations. The first topic of this review compares enzyme-induced transformations and receptor binding in terms of the appropriate assumptions. The second topic considers the complication of adding a competitive inhibitor as an enzyme substrate or a receptor ligand and the subtleties of inferring the equilibrium dissociation constant from the concentration of inhibitor (for example unlabeled drug) that leads to the midpoint, IC50, of an inhibition curve. Receptor binding may be measured directly by a concentration assay or as a pharmacodynamic response variable.
Original language | English (US) |
---|---|
Pages (from-to) | 819-826 |
Number of pages | 8 |
Journal | Nuclear Medicine and Biology |
Volume | 30 |
Issue number | 8 |
DOIs | |
State | Published - Nov 2003 |
Externally published | Yes |
Keywords
- Cheng-Prusoff equation
- Enzyme kinetics
- IC
- Kinetic modeling
- Pharmacodynamic models
- Receptor kinetics
ASJC Scopus subject areas
- Molecular Medicine
- Radiology Nuclear Medicine and imaging
- Cancer Research