[Ontogeny of pancreatic gastrin cells in neonatal rat]

It is well known that gastrin immunoreactive cells are observed in the fetal and postnatal rat pancreas. The role of the gastrin cells is unknown, however, it has been suspected that pancreatic gastrin may influence the development of pancreas and the gastrointestinal tract. The present study shows the localization of pancreatic gastrin cells and the ability of auto-proliferation of them in development. Gastrin cells were seen in 0-d to 2-wk-old rats in islet and in 0-d to 4-wk-old rats among exocrine cells. The ratio of gastrin cells to islet cells decreased in neonatal development and in rats older than 14-d gastrin cells were never observed in islet. Labeling indices of pancreatic gastrin cells after one injection of tritiated thymidine were 2.6% to 4.6% for 10 days after birth. It was suggested that gastrin cells have the ability of autoproliferation for 10 days after birth.