In vitro secretion of gastrin, insulin, and glucagon in tissue cultures of pancreas from a child with neonatal intractable hypoglycemia.

Small pieces of pancreatic tissue were obtained at surgery from a subtotal pancreatectomy performed in a 45-day-old child suffering from intractable neonatal hyperinsulinic hypoglycemia. Histological examination was performed using aldehyde fuchsin, Grimelius', and Hellerström-Hellman's stainings, and immunoperoxidase labeling of insulin and gastrin. The pancreatic tissue before explantation showed numerous and sometimes hyperplastic islets, together with isolated insulin-, glucagon-, and gastrin-containing cells scattered among the exocrine tissue, in aspects similar to "B cell nesidioblastosis." These features could be interpreted as an acinoinsular transformation and/or an embryonic malformation. Extralobular endocrine islet formation by budding from ductular structures was evoked, suggesting the persistency of embryonic properties. The pieces were cultivated on rooster plasma coagulum covered with culture medium. In vitro, endocrine cells survived for 43 days, with outgrowth from the explant and with retention of their secretory abilities. After each medium renewal, radioimmunoassays were performed on the culture medium; they showed that insulin and glucagon secretions decreased with time. On the contrary, secretion of immunoreactive gastrin progressively increased, and kept up to 43 days, with subcultures. Some explants developed in a peculiar way, outgrowing as epithelial layers rich in gastrin-secreting cells as indicated by radioimmunoassays performed after they were reexplanted.