Insulin-releasing activity and successful transplantation of pancreatic islets preserved by tissue culture.

Preserving pancreatic islets for 7 days by a making use of the organ culture, we studied the insulin-releasing activity at the time of administration of glucose and various digestive tract hormones for the purpose of clarifying the function of preserved pancreatic islets. Furthermore, we transplanted pancreatic islets preserved for 3 to 5 days into the portal vein of rats with streptozotocin-induced diabetes and reached the following conclusions: (1). The islets of Langerhans of the pancreas responded well to glucose up to the seventh day of preservation and showed patterns similar to those of fresh pancreatic islets with respect to both the dose response and the time response. (2). Preserved pancreatic islets of the pancreas had insulin-releasing activity almost equal to that of fresh pancreatic islets against stimulation by glucagon, tolbutamide, and various digestive tract hormones. (3). Rats with streptozotocin-induced diabetes showed a marked improvement in blood glucose and urine glucose following transplantation of preserved pancreatic islets into the portal vein, and this effectiveness persisted for 6 to 8 weeks.