Alpha-, Delta- and PP-cells: Are They the Architectural Cornerstones of Islet Structure and Co-ordination?

摘要: Islet non-β-cells, the α- δ- and pancreatic polypeptide cells (PP-cells), are important components of islet architecture intercellular communication. In α-cells, glucagon is found in electron-dense granules; granule exocytosis calcium-dependent via P/Q-type Ca2+-channels, which may be clustered at designated cell membrane sites. Somatostatin-containing δ-cells neuron-like, creating a network for intra-islet Somatostatin 1-28 1-14 have short bioactive half-life, suggesting inhibitory action paracrine signaling. PP-cells most infrequent type. The embryologically separate ventral pancreas anlage contains PP-rich islets that morphologically diffuse α-cell deficient. Tissue samples taken from head region unlikely to representative whole pancreas. PP has anorexic effects on gastro-intestinal function alters insulin secretion. disrupted rodent diabetic models, primates human Typ...