The effect of streptozotocin-induced diabetes on pituitary and hypothalamic endorphin equivalents.

This study examines the effect of experimentally induced diabetes mellitus in rats on tissue concentrations of opioid peptides in the neurointermediate lobe (NIL), anterior pituitary (AP) and hypothalamus. Diabetic animals were found to have a marked increase in endorphin equivalents, measured by opiate receptor binding assay, in the NIL whereas no change was observed in beta endorphin-like immunoreactivity (beta ELI) or ACTH measured by RIA. These results may indicate the presence of a feedback mechanism and suggest the possibility that opioid peptides may be physiologically important in the maintenance of glucose homeostasis.