Somatostatin-like immunoreactivity is found in dendritic guard cells of human sweat ducts.

Somatostatin is reported in a new population of human sweat duct cells. The epithelial content of somatostatin-like immunoreactivity in normal human skin from various sites of the body was investigated using indirect immunofluorescence. With this methodology we found round-to-oval somatostatin-immunoreactive cells situated outside the lining sweat duct cells at the level of the stratum spinosum. The cells had processes that were clearly directed towards the duct lumen, passing between the lining duct cells. This finding raises new questions and ideas about somatostatin's role in the skin, and could point to a possible involvement of somatostatin in immune defense, sweat secretion modification, antiproliferation, or other actions.