Born 18 May 1901; died 11 Dec 1978 at age 77.
American biochemist who was awarded the Nobel Prize for Chemistry in 1955 for his work on biochemically important sulphur compounds, especially for the first synthesis of a polypeptide hormone. Underneath the brain, the pituitary gland is well-protected and, in man about as big as a bean. It secretes several hormones, that is, substances which regulate important physiological functions. These are built up from amino acids in the same way as proteins, but with a far lower molecular weight. Vigneaud isolated and synthesized two pituitary hormones: vasopressin, which acts on the muscles of the blood vessels to cause elevation of blood pressure; and oxytocin, the principal agent causing contraction of the uterus and secretion of milk.