[Differentiation of the pancreatic endocrine cells of the white rat in the composition of the epithelium of excretory ducts].

Endocrine cells of beta and alpha types have been revealed in the ductal epithelium of the pancrease in rats from 1 to 20 days of the postnatal development by means of electron microscopy. Owing to various degree in differentiation of insulocytes, transitory forms existing between the ductal cells and the endocrinic elements, it is possible to consider the ductal epithelium as one of the sources for formation of the pancreatic islets and to think about the entodermal origin of the endorcrine part of the pancreas.