The effects of thermal stimulation on the ultrastructure of the human atrichial sweat gland. II. The duct.

The duct of the human atrichial sweat gland, after thermal stimulation, exhibited increased cytoplasmic vesiculation, particularly of the luminal cells, a widening of the intercellular spaces, and the presence of particulate matter in the lumen. The luminal cells of the coiled zone also displayed varying degrees of apical disruption, most probably due to filtration of cell fluid through the terminal web of microfilaments. This zone seems to have a secretory as well as an absorptive role. Specialized junctions (intercellular bridges, gap junctions and tight junctions) were found amongst the basal and luminal cells of the wall of the ascending duct.