One hundred years of hormones.

In June 1905, Ernest Starling, a professor of physiology at University College London, UK, first used the word ‘hormone’ in one of four Croonian Lectures— ‘On the chemical correlation of the functions of the body’—delivered at the Royal College of Physicians in London. Starling defined the word, derived from the Greek meaning ‘to arouse or excite’, as “the chemical messengers which speeding from cell to cell along the blood stream, may coordinate the activities and growth of different parts of the body” (Starling, 1905). Starling (Fig 1) was a brilliant experimentalist, and these prestigious lectures were in recognition of his work—much of it in collaboration with his brother-in-law William Bayliss—on the effects of innervations and pancreatic secretion on the intestine. Since Starling coined the word, the concept of hormones has spawned immense interest in a wide range of research fields, ranging from chemistry to molecular biology to epidemiology (Baulieu & Kelly, 1990; Turner & Bagnara, 1971). In addition to purely scientific advances, the study of hormones has led to enormous benefits to human health, social and economic progress, such as contraception, in vitro fertilization (IVF) and recombinant human hormones. More recently, the topic of hormones and hormonally regulated metabolism and development has also found interest among public health experts and the larger public, after concerned scientists in the USA hypothesized that various man-made chemicals could interfere with the hormonal system to cause a wide range of diseases and disorders. The nature and work of chemical messengers in the body had already attracted the interest of scientists before Starling. Experimental work by pioneers such as Arnold Adolphe Berthold in Germany and Claude Bernard in France, in the middle of the nineteenth century, established the concept that some sort of chemical communication takes place between different organs in an animal. Later in the same century, several physicians described the successful treatment of patients with certain disorders by administering extracts of animal endocrine tissues, such as the thyroid, adrenal glands and pancreas; they subsequently showed that these disorders were due to hormonal deficiencies.