Peptides and neuronal function

Abstract

In 1936, von Euler described the properties of an extract prepared from brain and gut which had the form of a white powder. This extract became known as substance P (SP), and it is discussed later in this chapter. The observation which was to prove to be of great significance was that the biological activity of substance P could be destroyed by trypsin, thus showing that substance P was a peptide. Some 30 years later, Harris showed that the release of hormones from the anterior pituitary was under the control of blood-borne factors. These blood-borne factors were released from the hypothalamus and carried to the anterior pituitary by a portal system. These factors were shown to be released from neurones in the hypothalamus, and furthermore, they were shown to be peptides. These observations led to the suggestion that peptides released from nerves could act as neurotransmitters.