The existence of the
hormone gastrin in the distal stomach (antrum) has been known for almost 110 years, and the physiological function of this amidated
peptide in regulating gastric acid secretion via the
CCK2 receptor is now well established. In this brief review we consider important additional roles of
gastrin, including regulation of genes encoding
proteins such as
plasminogen activator inhibitors and
matrix metalloproteinases that have important actions on extracellular matrix remodelling. These actions are, at least in part, effected by paracrine signalling pathways and make important contributions to maintaining functional integrity of the gastric epithelium. Recent studies also provide support for the idea that
gastrin, in concert with other
hormones, could potentially contribute a post-prandial
incretin effect. We also review recent developments in the biology of other
gastrin gene products, including the precursor
progastrin, which causes proliferation of the colonic epithelium and in certain circumstances may induce
cancer formation.
Glycine-extended biosynthetic processing intermediates also have proliferative effects in colonic mucosa and in some oesophageal
cancer cell lines. Whether these additional gene products exert their effects through the
CCK2 receptor or a separate entity is currently a matter of debate.