Tissue binding refers to the interaction between drugs and intracellular, extracellular, membrane, or receptor proteins in various organs, affecting drug distribution and elimination.
Mechanism of Tissue Protein Binding
Intracellular Binding: Drugs bind to intracellular proteins (e.g., enzymes, nuclear proteins), influencing drug action within cells.
Extracellular Binding: Interaction with extracellular matrix proteins (e.g., collagen, fibronectin) affects drug retention in tissues.
Membrane Binding: Drugs bind to transporters and ion channels, affecting their cellular uptake and distribution.
Receptor Binding: Specific drugs bind to receptors to trigger a pharmacological response, which can be reversible or irreversible.
Clinical Significance of Drug Binding
High plasma protein binding restricts drug distribution and slows elimination.
Extensive tissue binding may prolong drug action or cause toxicity.
Drug displacement from plasma proteins can increase free drug levels, affecting efficacy and safety.
