Ultrastructure of monolayer cultures of pancreatic islet cells

Summary Isolated islet cells from obese-hyperglycemic mice and normal guinea-pigs were culturedin vitro for periods of up to 7 days. Ultrastructural investigation showed that the cultured cells retained the morphologic characteristics of islet cellsin vivo. ₂-cells and -cells could be identified in explants from both obese-hyperglycemic mice and normal guinea-pigs. The most distinctive feature of the cultured islet cells was a marked degranulation of the -cells of both species. The degree of degranulation was not correlated with the glucose concentration in the incubation medium.This work was supported by the Swedish Medical Research Council (B69-12X-2297-02 and B69-12X-109-05), the United States Public Health Service (AM-12535) and the Medical Faculty, University of Uppsala.