Solute and Water Secretion in Sweat *

Open Access
Publisher Website
Google Scholar
Abstract
Employing a new technique of sweat collection where mineral oil is used as a vapor barrier it is shown that (1) sweat from the cat foot pad is slightly hypertonic and has a sweat to serum urea ratio of one, (2) the osmolality of sweat secreted by single glands in man is similar, (3) the sweat to serum urea ratio which is greater than one in man is independent of osmotic gradients in the same subject. Direct cryoscopic studies revealed that precursor fluid of sweat in cat and man is hypertonic. Because of the anatomic and physiologic differences between the sweat gland of cat and man, it is suggested that in man the proximity of the coiled duct to the secretory segment plays a role in the production of hypotonic sweat.