Direct intercellular communication in health and disease: an overview

Direct intercellular communication (cell to cell coupling) is a mechanism for the local transit of information between cells and supplements the endocrine and nervous systems. Electrophysiological, biochemical, histological and cell culture techniques have established the widespread existence of coupling in mammalian tissues, and the importance of the gap junction has been recognised. Information is carried in the form of ions and small molecules between cells, and sensitive apparatus exists within each cell for controlling the permeability of the junctional membrane. The system may be important in the control and co-ordination of cellular metabolism and growth in the embryo and in adult tissues. Disorders of direct intercellular communication may be important in the pathogenesis of some diseases, in particular cancer.