Incorporation of Human Chorionic Gonadotropin Alpha-Subunit into Different Types of Granule in Stomach Endocrine Cells

In order to demonstrate the ultrastructural localization of the α subunit of human chorionic gonadotropin (hCG) in the stomach mucosa, an immunoelectron microscopic study was performed using formalin-fixed specimens. In pyloric glands, α hCG-positive granules were irregular in outline, with a mean area and maximum diameter of 2.857 × 10⁴ nm² and 218.4 nm, respectively. In fundic glands, the granules had a smoother outline and were larger in both area and maximum diameter (3.943 × 10⁴ nm², 246.8 nm) than those of pyloric glands (p <0.001). In the atrophic fundic glands of non antral gastritis, the αhCG granules showed a differece in shape; more elliptical granules appeared to be increased, as indicated by the higher value of the axial ratio (1.452) and lower value of D (1.862) (log₁₀ area ∞ D log₁₀ perimeter) compared with those in pyloric (1.231, 1.968) and fundic glands (1.148, 1.979) (p< 0.001). The a-subunit of hCG is thus Incorporated into different types of endocrine cell in pyloric and fundic glands, and the granule morphology appears to differ in hyperplastic αhCG cells of non-antral gastritis. Acta Pathol Jpn 39: 737-742, 1989.