AJP - Regulatory, Integrative and Comparative Physiology, Vol 252, Issue 1 166-R180, Copyright © 1987 by American Physiological Society
Morphology and development of an apoeccrine sweat gland in human axillae
K. Sato, R. Leidal and F. Sato
Evidence is presented that in adult human axillae there exists a third type
of sweat gland tentatively designated as the apoeccrine sweat gland. This
type of gland shows a segmental or diffuse apocrinelike dilatation of its
secretory tubule but has a long and thin duct which does not open into a
hair follicle. The electron microscopy of its dilated segment is often
indistinguishable from that of the classical apocrine gland. The less
remarkably dilated segment of the apoeccrine gland tends to retain
intercellular canaliculi and/or dark cells. These apoeccrine glands are
consistently present in adult human axillae regardless of sex or race. In
the axillae of the two 6-yr-old subjects, both classical apocrine and
eccrine glands were present but no apoeccrine glands were found. Between
8-14 yr of age, the number of large eccrine glands with or without partial
segmental dilatation gradually increased. At 16-18 yr of age, the number of
apoeccrine glands increased to as high as 45% of the total axillary glands.
The data support the notion that apoeccrine glands develop during puberty
in the axillae from eccrine or eccrinelike sweat glands.
