“Receptive Substances”: John Newport Langley (1852–1925) and his Path to a Receptor Theory of Drug Action

Abstract

The concept of specific receptors that bind drugs or transmitter substances onto the cell, thereby either initiating biological effects or inhibiting cellular functions, is today a cornerstone of pharmacological research and pharmaceutical development. Yet, while the basic ideas of this concept were first explicitly formulated in 1905 by the Cambridge physiologist John Newport Langley (1852–1925), drug receptors remained hypothetical entities at least until the end of the 1960s. Without doubt, the development of receptor-subtype specific pharmaceuticals—especially the beta-adrenergic receptor antagonist propranolol (introduced in 1965)—promoted the acceptance of the receptor concept in pharmacology. It was only in the 1970s, however, that receptors began to be isolated as specific proteins of the cell membrane and that their composition and conformation began to be explored. During the last twenty years the modern techniques of molecular biology have helped to determine the genetic basis of receptor proteins, to identify their amino acid sequences, and to further elucidate their remarkable structural diversity as well as their similarities and evolutionary relationships. Numerous receptor types and subtypes have since been characterized.