Transplantation of preserved pancreatic islets into the portal vein of rats.

Langerhans islets were isolated from the exocrine pancreata of Wistar rats by the improved collagenase-digestion method. The isolated islets were preserved in a tissue culture medium for seven days. Transplantation of these preserved islets into the portal vein of streptozotocin-induced diabetic rats resulted in a significant reduction of hyperglycemia, polyuria and glucosuria, and a restoration of weight gain. It was found that these effects could be maintained for 16 weeks. In order to normalize the K-values and plasma insulin levels, at least 600 islets had to be transplanted into each diabetic rat.