Neuronal communication.

Abstract

Since the initial description of simple chemical transmission systems involving one neurotransmitter, its respective receptor and second messenger, there has been an explosive growth in our understanding of the components and complexity of signal transduction systems involved in neuronal communication. Why did neurons develop such a complex signaling system, including coreleased neuromessengers, multiple receptor subtypes and interconnected transduction mechanisms? How is the specificity of a message encoded into a single neuromessenger maintained when the transduction pathways are shared by so many other molecules? How does a cell discriminate between the message carried by the same molecule conveying short-term responses, endocrine messages, or signals for growth and differentiation? In the following article, the author tries to address these questions by providing a framework for cell-to-cell communication based on basic principle of information theory. It is suggested that many of the observed mechanisms of electrical and chemical transmission are a consequence of evolutionary strategies to develop efficient encoding and rapid, error-free transmission of information between cells.