Isolation of two minigastrins from Zollinger-Ellison tumour tissue.

A pair of gastrin tridecapeptides (;minigastrins') have been isolated from Zollinger-Ellison tumour tissue; they correspond to the fragment 5-17 of the heptadecapeptides isolated from the same source. In one (type II) the tyrosine residue present is sulphated, in the other (type I) it is not. The proportion of types I and II is approximately 2:1 similar to that for the ;big' gastrins and the heptadecapeptides isolated from the same source and from human antral mucosa. Both minigastrins are potent stimulants of gastric acid secretion. Immunological evidence exists to indicate that both are present as circulating forms of the hormone gastrin in patients with the Zollinger-Ellison syndrome and in fed normal subjects.