The morphology and function islets isolated from rat pancreases with short-term (16 days) exocrine atrophy was investigated. It was found that this type of atrophy induced changes in the shape and morphological structure of pancreatic islets. However, the function of isolate islets did not change, as investigated by the basal or glucose-stimulated secretion of insulin, glucagon and somatostatin, and by the CCK-stimulated secretion of insulin. We conclude that the rat pancreas brought to atrophy by a short-term ligation of the pancreatic duct can be considered as a rich source of functionally viable islets.