Experimental hypoglycemizing tumor of B-cells of Langerhans islets produced by the combined action of streptozotocin annd nicotinamide in the rat.

Young male and female Wistar-Velaz rats were treated with streptozotocin-nicotinamide combination according to the method of Rakieten and examined periodically for 23 months for fasting and postprandial glycemia, by intravenous, intraperitoneal or intragastric glucose tolerance and tolbutamide tests with the aim to detect in vivo the experimentally produced nesidiomas. One male rat with severe hypoglycemia, apparent first on tolbutamide test after twelve months, later also on glucose tolerance test and fasting hypoglycemia associated with paraplegia with macroscopically and microscopically documented nesidioma is described. The exstirpation of this nesidioma was followed first by normalization and later by development of latent diabetes.