Different physiological signatures of sweat gland secretory and duct cells in culture

Human eccrine sweat gland cells grown in culture were found to lose their characteristic shape, becoming flattened and organized into multilayers. The resting membrane potentials of the cultured secretory cells (-35 +/- 2 mV, n = 36) were significantly higher than those measured for cultured duct cells (-22 +/- 1 mV, n = 58, P less than or equal to 0.01). When the cholinergic agonist methacholine (10(-5) or 10(-6) M) was administered, the cultured secretory cells could be distinguished unequivocally by their atropine-sensitive hyperpolarizing response (-20 +/- 2 mV, n = 43), whereas no cultured duct cells responded. When the sodium conductance antagonist amiloride (10(-5) or 10(-6) M) was administered, 44% of cultured secretory cells responded by hyperpolarization (-8 +/- 1 mV, n = 8), whereas 87% of cultured duct cells hyperpolarized (-15 +/- 1 mV, n = 46) and by a significantly greater margin (P less than or equal to 0.01). Substitution of chloride with gluconate in the bathing medium caused membrane potential depolarization in both cultured secretory and duct cell populations, which is consistent with the presence of a chloride conductance in the plasma membrane. The beta-adrenoceptor agonist isoproterenol induced a transient hyperpolarization of 5-10 mV in three out of six cultured secretory cells tested but had no effect on cultured duct cells.

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Novel exocrine glands in the hindleg tarsi of the ant Nothomyrmecia macrops

Australian Journal of Zoology ◽

10.1071/zo00050 ◽

2000 ◽

Vol 48 (6) ◽

pp. 661 ◽

Cited By ~ 2

Author(s):

Johan Billen ◽

Fuminori Ito ◽

Christian Peeters

Keyword(s):

Golgi Apparatus ◽

Secretory Cell ◽

Anterior Part ◽

Duct Cell ◽

Exocrine Gland ◽

Secretory Cells ◽

Exocrine Glands ◽

The Third ◽

Duct Cells

The third tarsomere of the hindlegs of both workers and queens of Nothomyrmecia macrops is almost entirely filled with a hitherto unknown exocrine gland (which does not occur in the closely related Myrmecia). Each of the approximately 30 secretory cells is connected to the outside via a duct cell. These open individually via large cuticular pores at the mesoventral side of the anterior part of the tarsomere. The diameter of the duct cells is narrow near the secretory cell, but gradually increases towards their opening site. The rounded secretory cells show a well developed Golgi apparatus and numerous clear vesicles. The function of this gland is not yet known, although its opening site may be indicative of the deposition of marking substances. At the mediodistal side of tarsomeres 2, 3 and 4 in the three pairs of legs, a glandular thickening of the epidermal epithelium occurs; this represents another novel exocrine structure in ants. This epithelial gland occurs in both Nothomyrmecia and Myrmecia.

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Ultrastructural localization of ouabain-sensitive, K-dependent p-nitrophenyl phosphatase activity in monkey eccrine sweat gland.

Journal of Histochemistry & Cytochemistry ◽

10.1177/36.8.2839572 ◽

1988 ◽

Vol 36 (8) ◽

pp. 1023-1030 ◽

Cited By ~ 15

Author(s):

K Saga ◽

K Sato

Keyword(s):

Enzyme Activity ◽

Cell Membrane ◽

Sweat Gland ◽

Eccrine Sweat Gland ◽

Secretory Cells ◽

Membrane Processes ◽

Basolateral Membranes ◽

Ductal Cells ◽

Sweat Secretion ◽

Eccrine Sweat

We studied the electron microscopic localization of ouabain-sensitive, potassium-dependent p-nitrophenyl phosphatase (K-pNPPase) activity of the Na K-ATPase complex in Rhesus monkey eccrine sweat gland by use of the one-step lead citrate method of Mayahara et al. (Histochemistry 1980; 67:125). Reaction product was observed predominantly in the cytoplasmic side of the basolateral membranes of clear (secretory) cells, especially in the interdigitating membrane folds in the basal labryinth, and were completely abolished by 10 mM ouabain or by removal of K+. Little or no enzyme activity was noted in membrane processes in the intercellular canaliculi and in the secretory coil lumen. Basolateral membranes of the dark cells also showed moderate enzyme activity. The myoepithelial cell membrane was devoid of reaction product, except in a few membrane processes arising from the inner aspect of myoepithelial cells. In the coiled duct, K-pNPPase activity was present predominantly in the entire cell membrane of the peripheral ductal cells. The predominantly basolateral distribution of Na-K-ATPase in the eccrine sweat secretory cells is consistent with the concept that a Na-K-Cl co-transport model may be involved in the mechanism of eccrine sweat secretion.

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