Suppression of Plasma Immunoreactive Insulin in Rats given D-Mannoheptulose

Abstract

SIMON and co-workers^1–3 produced marked hyperglycaemia in the fasting rat with a single injection of D-mannoheptulose, a seven carbon sugar found in avocados. Their work suggests that heptulose blocks normal pancreatic secretion of insulin in response to glucose and that it induces gluconeogenesis. Coore et al.⁴ have demonstrated in rabbit pancreas slices that mannoheptulose blocks the glucose-stimulated release of insulin. The present investigation provides evidence that in the intact rat mannoheptulose suppresses the increase in plasma immunoreactive insulin (IRI) normally elicited by hyperglycaemia.