Glucose Metabolism of the Isolated Eccrine Sweat Gland

Abstract

A B S T R A C T This paper attemiipts to fturther clarify the characteristics of Mecholyl-or epinephrine-stimulated glucose metabolism in the isolatefl monkey eccrinie sweat gland with special emphasis on its relationship to increased sodium transport. The Mecholyl-or epinephrine-stimulated glucose metabolism (as estimated by either lactate or "CO2 production or both) is seen only in the secretory coil and not in the duct. It is markedly suppressed in thie absenice of glucose, Na', or K+. It is inhibited by ouabain (10' M) and partially suppressed in a low-sodium (40 mMI), high-potassituni (100 mM) medium.2,4-dinitrophenol (10-' A) reverses ouabain-induced inhibition of lactate and 1"CO2 production but only partially reverses inhibitioni induced by Na+ + K+ deprivation, indicating that metabolic inhibition by ouabain is secondary to the inhibition of sodium transport. There is no synergism between Miecholyl and epiniephrine. The absence of any significant inhibitorv effects by acetazolamide (Diamox) or HCO3-free media suggests that H+ transport may not be important in sweat gland function. In contrast to a report by Wolfe et al., human eccrine sweat glands show considerable oxidative activity ("CO2 production of 0.42-0.72 nimol/glanid/lh). These observations are discussed in terms of the linkage between sweat gland energy metabolism an(d sodium transport.

Identification of Stem Cell Populations in Sweat Glands and Ducts Reveals Roles in Homeostasis and Wound Repair

“…hydrogen and protein transport, that were not seen in the myoepithelial signature (compare Figures 6D and 6E). Another distinction was the preponderance of luminal genes involved in carbohydrate metabolism, a link made previously from pharmacologic studies (Sato and Dobson, 1973). More extensive lists for myoepithelial and luminal signature genes are shown in Table S1.…”

L‐lactic acid: a human‐signifying host cue for the anthropophilic mosquito Anopheles gambiae

“…l ‐lactic acid on the human skin is an end‐product of glycolysis during anaerobic metabolism of the myoepithelial cells of the eccrine sweat glands (Sato & Dobson, 1971, 1973). Eccrine glands are, in contrast with apocrine glands, not associated with hair follicles and only in humans, where they occur all over the body, do they play an important role in thermoregulation (Robertshaw, 1991).…”

“…Possibly aerobic glucose metabolism predominates over anaerobic metabolism in apocrine sweating. Both types of glucose metabolism exist in primate eccrine glands (Sato & Dobson, 1971).…”

The evolution of eccrine sweat gland research towards developing a model for human sweat gland function

“…The advent of a skin punch biopsy technique meant samples could be obtained from human volunteers for structural and functional investigations of the eccrine gland in vitro, rather than using animal tissues. Reports described eccrine glands as having two morphologically and functionally different components; a secretory coil and a ductal segment that produced a hypotonic sweat, through ductal electrolyte reabsorption that could be inhibited by blocking sodium transport …”

“…Previously, ethical and practical issues limited a deeper understanding of human sweat gland function; however, the advent of enzymatic and microdissection techniques to isolate intact functional sweat glands from tissue samples changed that. Initial reports described the function of entire intact glands or the secretory coil/duct separately from rats and simians .…”