scholarly journals 332 New Methods for the Functional In Vitro Characterization of Isolated Human Eccrine Sweat Glands

2021 ◽  
Vol 141 (10) ◽  
pp. S206
Author(s):  
T.F. Buck ◽  
T. Kisch ◽  
C. Kruse ◽  
M. Brandenburger
1981 ◽  
Vol 240 (1) ◽  
pp. R44-R51 ◽  
Author(s):  
K. Sato ◽  
F. Sato

Pharmacologic responsiveness of the eccrine sweat gland has never been studied under well-defined in vitro experimental conditions. Using isolated cannulated single monkey palm eccrine sweat glands, the dose response to both cholinergic and alpha- and beta-adrenergic agents and the effects of various antagonists on agonists were studied. The maximal sweat rate was highest after stimulation with cholinergic agonists, was lower with the beta-adrenergic agonist, and was least with the alpha-adrenergic agonist. Each secretory response was inhibited by its specific antagonist. Attempts to demonstrate the spare receptor, if any, by means of preincubation of the glands with N-(2-chlorethyl)dibenzylamine (Dibenamine) were unsuccessful. From the hyperbolic dose-response curves the values for KA and KB, dissociation constants for agonists and antagonists, respectively, were thus tentatively estimated according to Clark's classical receptor theory. Schild plots for each agonist-antagonist interaction produced straight lines with slopes of near unity, indicating the adequacy of the methodology. It was concluded that the isolated eccrine sweat glands retain their pharmacologic viability in vitro and show responsiveness to cholinergic as well as both alpha- and beta-adrenergic stimulations.


2005 ◽  
Vol 125 (3) ◽  
pp. 428-444 ◽  
Author(s):  
Lutz Langbein ◽  
Michael A. Rogers ◽  
Silke Praetzel ◽  
Bernard Cribier ◽  
Bernard Peltre ◽  
...  

1984 ◽  
Vol 247 (3) ◽  
pp. C234-C239 ◽  
Author(s):  
K. Sato ◽  
F. Sato

The possibility that guanosine 3'5'-cyclic monophosphate (cGMP) may be an intracellular mediator of cholinergic stimulation [methacholine chloride (MCh)] was explored by comparing the relationship between the time course of cGMP accumulation and sweat secretion by use of isolated monkey palm eccrine sweat glands. Isolated sweat glands were incubated with MCh or other agents, and tissue levels of cGMP were determined by radioimmunoassay. In parallel experiments, sweat secretion was induced from cannulated single sweat glands in vitro. Stimulation with MCh produced a Ca-dependent transient elevation of cGMP level from 10 to 80 fmol/gland, peaking at 1-2 min but returning to the basal level by 5 min. The MCh-induced cGMP level was dose dependent and was inhibited by atropine. Ionophore A23187 (2 X 10(-4) M), however, caused persistent elevation of cGMP level for at least 20 min. Neither 10(-4) M MNNG, which elevated the cGMP level comparably with MCh stimulation, nor 8-bromo-cGMP (2 mM) induced sweat secretion. Thus although a parallelism between the cGMP level and sweating rate appears to hold for the initial stage of MCh-induced sweating, it does not hold for the steady state of sweat secretion. Data could not be interpreted to favor the notion that cGMP may be the intracellular mediator of cholinergic sweat secretion.


1981 ◽  
Vol 241 (3) ◽  
pp. C113-C120 ◽  
Author(s):  
K. Sato ◽  
F. Sato

The role of Ca2+ in eccrine sweat secretion was studied using isolated cannulated monkey palm eccrine sweat glands in vitro. Removal of Ca2+ from the incubation medium promptly abolished sweat secretion induced by methacholine or phenylephrine. In contrast, isoproterenol-induced sweat secretion lasted from 40 to 220 min in a Ca2+-free medium. The methacholine-induced maximal sweat rate was a hyperbolic function of the Ca2+ concentration in the bath and reached a plateau at 1 mM Ca2+. Higher Ca2+ concentrations rather suppressed the secretory rate. The Ca2+ ionophore A23187, but not X537A, at 3 X 10(-6) M induced copious prolonged sweat secretion after a latent period of 10 min. A23187-induced sweat secretion was not inhibited by either atropine or propranolol. D 600 (methoxyverapamil) at 10(-3) M inhibited sweat secretion induced by methacholine or by isoproterenol, although the latter lasted longer than methacholine sweating (20 vs. 5 min) in the presence of D 600. The data support the notion that Ca2+ influx into the cell plays a crucial role in cholinergic and alpha-adrenergic sweating, whereas a partial supply of Ca2+ for isoproterenol-induced sweating is derived from an intracellular store.


Author(s):  
J. V. Briggman ◽  
J. Bigelow ◽  
H. Bank ◽  
S. S. Spicer

The prevalence of strands shown by freeze-fracture in the zonula occludens of junctional complexes is thought to correspond closely with the transepi-thelial electrical resistance and with the tightness of the junction and its obstruction to paracellular flow.1 The complexity of the network of junc¬tional complex strands does not appear invariably related to the degree of tightness of the junction, however, as rabbit ileal junctions have a complex network of strands and are permeable to lanthanum. In human eccrine sweat glands the extent of paracellular relative to transcellular flow remains unknown, both for secretion of the isotonic precursor fluid by the coil and for resorption of a hypertonic solution by the duct. The studies reported here undertook, therefore, to determine with the freeze-fracture technique the complexity of the network of ridges in the junctional complexes between cells in the secretory coil and the sweat ducts. Glands from a patient with cystic fibrosis were also examined because an alteration in junctional strands could underlie the decreased Na+ resorption by sweat ducts in this disease. Freeze-fracture replicas were prepared by standard procedures on isolated coil and duct segments of human sweat glands. Junctional complexes between clear cells, between dark cells and between clear and dark cells on the main lumen, and between clear cells on intercellular canaliculi of the coil con¬tained abundant anastomosing closely spaced strands averaging 6.4 + 0.7 (mean + SE) and 9.0 +0.5 (Fig. 1) per complex, respectively. Thus, the junctions in the intercellular canaliculi of the coil appeared comparable in complexity to those of tight epithlia. Occasional junctions exhibited, in addition, 2 to 5 widely spaced anastomosing strands in a very close network basal to the compact network. The fewer junctional complexes observed thus far between the superficial duct cells consisted on the average of 6 strands arranged in a close network and 1 to 4 underlying strands that lay widely separated from one another (Fig. 2). The duct epitelium would, thus, be judged slightly more "leaky" than the coil. Infrequent junctional complexes observed to date in the secretory coil segment of a cystic fibrosis specimen disclosed rela¬tively few closely crowded strands.


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