Further purification of gastrozymin and spectrum of activities.

Gastrozymin differed from secretin in several chromatographic and solubility characteristics. However, it showed a spectrum of activities which resembled those of secretin, including stimulation of pepsin, hepatic bile secretion, and pancreatic bicarbonate secretion. This study revealed differences in the quantitative ratios of these activities when induced by secretin or gastrozymin. In particular, if the ratio of the stimulation of pepsin secretion to that of pancreatic juice bicarbonate was 1:1 for secretin, it was 4:1 for gastrozymin. Further purification will show whether all these effects are induced by one molecule or by several peptides. It will also determine whether there is a structural relationship between gastrozymin and secretin or its precursor(s).