Expression of neural cell adhesion molecule (N-CAM) in rat islets and its role in islet cell type segregation

摘要: Endocrine cell types are non-randomly distributed within pancreatic islets of Langerhans. In the rat, insulin-secreting B-cells occupy core and surrounded by A-, D- PP-cells, secreting glucagon, somatostatin polypeptide, respectively. Furthermore, dissociated islet cells have ability in vitro to form aggregates with same cell-type organization as native (pseudoislets). These observations suggest that a differential expression adhesion molecules (CAMs) might characterize B- non-B-cells (A-, PP-cells), be part responsible for establishment maintenance architecture. Indirect immunofluorescence using antibodies against CAMs hormones was performed on serial sections splenic duodenal parts rat pancreas. Staining Ca(2+)-dependent CAM E-cadherin detected both exocrine endocrine tissue uniform over entire section, regions. By contrast, staining Ca(2+)-independent neural (N-CAM) restricted nerve endings. N-CAM stronger periphery, region composed mostly non-B-cells. Serial demonstrate strongly correspond glucagon polypeptide cells. Within pseudoislets also observed peripheral cells, corresponding