[Receptor-enzyme interactions. Kinetic characteristics].

The kinetic regularities characterizing the behaviour of enzyme-receptor systems underlying molecular mechanisms of transmission and transformation of current information at the cellular level are reviewed. The properties of receptors as molecular detectors responsible for chemical signal "recognition" are described, and the efficiency of enzyme-substrate and effector-receptor interactions is compared. The heterogeneity of receptor populations and kinetic approaches to their discrimination are considered. The principal mechanisms and problems of chemical signal amplification in coupled enzymatic reactions are discussed. The major properties of the ligand-receptor system and its relation to gene expression in receptors as well as mechanisms of cell response "quenching" are reviewed. Some kinetic regularities of desensitization of enzyme-receptor systems are discussed in terms of present-day concepts on desensitization as inactivation of enzyme-receptor systems in the reaction course.