Islet Formation during the Neonatal Development in Mice

摘要: The islet of Langerhans is a unique micro-organ within the exocrine pancreas, which composed insulin-secreting beta-cells, glucagon-secreting alpha-cells, somatostatin-secreting delta-cells, pancreatic polypeptide-secreting PP cells and ghrelin-secreting epsilon-cells. Islets also contain non-endocrine cell types such as endothelial cells. However, mechanism(s) formation poorly understood due to technical difficulties in capturing this dynamic event situ. We have developed method monitor beta-cell proliferation intact pancreas using transgenic mice beta-cells are specifically tagged with fluorescent protein. Endocrine proliferate contiguously, forming branched cord-like structures both embryos neonates. Our study has revealed long stretches interconnected islets located along large blood vessels neonatal pancreas. Alpha-cells span elongated islet-like structures, we hypothesize represent sites fission facilitate eventual discrete islets. propose that occurs by process following contiguous endocrine proliferation, rather than local aggregation or fusion isolated Mathematical modeling presented.