Functional alteration of the islet cells was investigated in dogs after the resection of different parts of the small intestine. Three weeks after jejunal or ileal resection, when the dogs might still have been in a catabolic state, insulin and pancreatic glucagon release in response to intravenously infused glucose and arginine was reduced. Three months after jejunal resection, both intravenous glucose tolerance and insulinogenic index in the intravenous glucose tolerance test were significantly below the preoperative values (P < 0.001, P < 0.05), while pancreatic glucagon release in response to arginine infusion showed almost normal levels in contrast to low response of insulin release. This functional alteration three months after jejunal resection was similar to that seen in diabetes meilitus. On the other hand, three months after ileal resection, insulin and pancreatic glucagon release was almost normal.
We conclude that the jejunum plays a more important role in the enteroinsular system than the ileum and that prolonged interruption of this enteroinsular axis can cause insular disorder and what could hypotheticaUy be called enterogenic chemical diabetes, in view of the altered glucose tolerance test and the alteration in insulin secretory response.