The ultrastructure and histophysiology of human eccrine sweat glands

The electron microscopy of human eccrine sweat glands has been studied before and after stimulation by pilocarpine iontophoresis. The identity of the dark and clear cells in the secretory segment as defined by Montagna et al. (23) was determined by studying serial sections, thin for electron microscopy and thick for light microscopy. Cells with numerous apical secretory vacuoles are termed mucoid (dark) cells, since these vacuoles stain positively for acid mucopolysaccharide. Clear cells are intimately associated with intercellular canaliculi. The "cuticular border" of surface cells of the duct is a condensation of tonofilaments and granules. Numerous mitochondria are concentrated in basal cells of the duct. The presence of mucoid cells in the secretory segment may bear on the interpretation of the pathologic findings in the disease cystic fibrosis of the pancreas, and suggests that this disease may be due to a basic disorder of mucopolysaccharide production. The possible roles of the various cellular components in the elaboration of sweat are discussed.

An electron microscopic study of eccrine sweat glands of the catfoot and toe pads--evidence for ductal reabsorption in the human

The eccrine sweat glands of the cat foot and toe pads have been studied by light and electron microscopy before and after stimulation with mecholyl. The ultrastructure of these glands in the cat is found to be entirely comparable to that in the human (13). The ultrastructure and staining properties of the secretory segment of the two species are identical. The ductal part of the feline gland is shorter and the ductal cells have only scant mitochondria as compared with the human. Since Brusilow et al. (1) have observed that the secretion of the cat foot pad is isotonic as compared with human sweat, which is hypotonic, and since the secretory segments of the two species are structurally identical, the striking difference in the morphology of the duct is regarded as being responsible for the difference in the chemistry of the secretion of the two species. Thus the duct in the human is capable of reabsorbing sodium and chloride.

An electron microscopic study of the human axillary apocrine gland

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A comparison between the number and distribution of functioning eccrine sweat glands in Europeans and Africans

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