Glycoprotein hormone alpha-subunit in human stomach.

To demonstrate the immunoreactive alpha-subunit of human chorionic gonadotropin (hCG) or glycoprotein hormones in non-neoplastic gastric mucosa, and to clarify the nature and significance of alpha-subunit-immunoreactive cells, immunohistochemical studies were performed on gastric mucosa using polyclonal antibodies for hCG alpha and beta, hLH beta, hFSH beta, hTSH beta, and gastrin, and a monoclonal antibody for hCG alpha. Surgically resected stomachs were classified as follows: nearly normal (Group A); antral gastritis (Group B); fundic gastritis with pseudopyloric glands (Group C); and intestinal metaplasia (Group D). Cells immunoreactive for the alpha-subunit were present in the pyloric glands and to a lesser extent in the fundic glands (Groups A and B). Almost all alpha-subunit-immunoreactive cells were nonreactive for the beta-subunits of the four glycoprotein hormones. alpha-subunit-immunoreactive cells corresponded to gastrin-containing cells in the pyloric glands, but were unrelated to gastrin in the fundic glands. In fundic gastritis, alpha-subunit-immunoreactive cells appeared to increase (Group C), and many hyperplastic foci were observed in atrophic glands with hyperplasia of the argyrophilic cells (Groups C and D). Isolated hCG alpha or the alpha-subunit of glycoprotein hormones may be present in the endocrine cells of gastric mucosa, and alpha-subunit-immunoreactive cells in the fundic glands seem to proliferate in fundic gastritis.