Abstract
The endocrine-like cells in the normal antro-pyloric mucosa of the human stomach were examined by the electron microscope. According to their fine structural characteristics, they were tentatively classified into the following seven types. Cell-type I has very electron dense and polymorphous secretory granules in the basal region. The narrow apical part has long microvilli. Cell-type II is triangular in shape. The granules are round and vary in diameter (300-600mμ) and in electron density. Cell-type III is triangular in form and has many round granules (130mμ in diameter) with high electron density. These granules are characterized by their uniform size and homogeneous appearance. Cell-type IV contains a prominent endoplasmic reticulum in the supranuclear region. Two kinds of granules are recognizable in the basal part: smaller ones (200mμ) which are dense, and larger ones (400mμ) which are pale and foamy. Cell-type V is in contact with the glandular lumen and contains numerous secretory granules with various densities. Cell-type VI is oval in shape and characterized by small granules (90-150mμ) with moderate density, localized in the basal region. Cell-type VII is round or spindle-shaped and has very long microvilli. In the infranuclear region there are a number of secretory granules which have some flues of low electron density and which are enclosed by a limiting membrane.
