[Endocrine cells of stomach epithelium in the ontogenesis of albino rats].

By means of the light and electron microscopy methods structural bases of differentiation and contents of endocrine cells of the stomach epithelium have been studied during the white rat pre- and postnatal development. The development of the endocrine epithelial cells occurs in parallel with the exocrinic ones. Endocrine EC-, G-, D-, P-cells are the first to be revealed in composition of the embryonal stomach epithelium, the others--during the early postembryonic period. The differentiation of the endocrine cells is characterized with asynchronism, is accompanied with a gradual development of organells, increasing amount of secretory granules and appearance of polarity in their distribution. By the 30th day of the postnatal development, the amount of the endocrine cells in the stomach epithelium increases by 5 times in comparison to those in the 1-day-old animals, with simultaneous reaching of the high level in specific differentiation.