Histochemical Evidence for Human Eccrine Sweat Duct Activity

Abstract

INTRODUCTION Previous simultaneous biochemical studies on blood and palmar sweat¹suggested that the eccrine sweat duct, instead of being a mere passive conductor of sweat to the surface of the skin, may play an active role in the sweating mechanism.^* Recently Araki and Ando⁶surmised from their multiple studies that the concentrating mechanism of urea existed in the sweat gland duct, and this surmise was strengthened by previous observations by Kuno and his coworkers. The latter noted abundant capillaries around the sweat duct, and also found that the dyes and iron which entered the duct from the surface by electrophoresis escape through the duct wall into surrounding tissues. They suggested the possibility that the duct reabsorbs water and other constituents of sweat secreted by gland cells. Nitta⁷explored the same possibility in his experiments on the changes in sweat constituents resulting