ABSTRACT
Although William Bayliss and Ernest Starling are credited with initiating the “physiological era” of GI endocrinology with their discovery of secretin in 1902, the true “biochemical era” awaited the development of more modern laboratory techinques for the purification and analysis of extracts from the GI mucosa. Approximately 30 “new” GI peptides have been identified over the past 30 years in specialized enteroendocrine cells, and in GI neuroendocrine cells. Many of these are also found in the CNS, leading to the concept of a brain-gut axis (Ch. 51). The full physiological significance of many of these newly discovered GI peptides is unknown.
