PROLIFERATING CELLS IN HUMAN ECCRINE AND APOCRINE SWEAT GLANDS

Morphological observations of sweat glands showed degenerated debris o f secretory cells in the secretory lumen in both apocrine and eccrine sweat glands. This suggested that dead secretory cells of human eccrin e and apocrine sweat glands were released into the lumen and replaced by other cells, However, we did not know which type of cells replaced lost secretory cells. Therefore, we studied the proliferating cells; i n human eccrine and apocrine sweat glands by labeling S-phase cells in vitro with 5-bromo-2'-deoxyuridine (BrdUrd) and by immunostaining pro liferation-associated proliferating cell nuclear antigen (PCNA) with a nti-PCNA monoclonal antibody, BrdUrd and anti-PCNA antibody labeled a few secretory cells in eccrine and apocrine sweat glands, but neither method labeled myoepithelial cells. Luminal and peripheral cells of th e eccrine and apocrine coiled duct were labeled with both BrdUrd and P CNA, However, we could not find any highly proliferative germinative c ells in coiled ducts. Our results suggest that lost secretory cells co uld be replaced by proliferation of secretory cells themselves rather than by proliferation of myoepithelial cells or duct cells.