A Role for Somatostatin in the Impaired Insulin Secretory Response to Glucose by Islets from Aging Rats

The purpose of this study was to investigate a possible contribution by somatostatin to the impairment in glucose-stimulated secretion of insulin during aging. Pancreatic islets of Langerhans were isolated from male Sprague-Dawley rats aged 2- to 24-months and challenged in vitro with effectors of insulin secretion. Concentrations of insulin, glucagon, and somatostatin were determined by radioimmunoassay. The impairment of glucose-stimulated secretion of insulin which characterizes islets isolated from aged rats may be overcome by treatment of islets with antibodies to somatostatin. Enhanced availability and/or effectiveness of endogenous pancreatic somatostatin during aging may be responsible for the modified pattern of glucose-stimulated secretion of insulin.