The effects of thermally-induced activity in vivo upon the ultrastructure and Na, K and Cl composition of the epithelial cells of sweat glands from patients with cystic fibrosis

The cholinergic regulation of potassium (86Rb+) permeability in sweat glands isolated from patients with cystic fibrosis

“…The present results, in common with those of an earlier microanalytical study (Wilson et al 1988), suggest that, at least in some patients, CF may induce abnormal cholinergic regulation of cellular potassium permeability in the sweat glands. In common with other exocrine organs Petersen & Gallacher, 1988), cholinergic responses of sweat glands appear to be mediated by increased [Ca2+]i (Bovell et al 1989a) and so, although we cannot exclude the possibility that the present findings may reflect abnormality in the potassium channels themselves, the data suggest strongly that CF may induce dysfunction of a [Ca2+]i-dependent control process.…”

“…This response was not observed in the sweat glands of patients with cystic fibrosis (CF) (Wilson, Elder, Sutton, Jenkinson, Cockburn, Montgomery, McWilliams & Bovell, 1988), a potentially lethal, genetic disease which is characterized by dysfunction of epithelial transport processes. In common with other exocrine organs ) the loss of potassium from the normal sweat gland reflects a secretagogue-evoked increase in cellular potassium permeability that is mediated by a rise in intracellular free calcium ([Ca2+]i) (Bovell, Elder, Jenkinson & Wilson, 1989 a).…”

“…The rate of efflux of this isotope was subsequently monitored during superfusion with a physiological salt solution (Bovell et al 1989a). Changes in efflux rate were assumed to reflect changes in cellular potassium permeability (Gallacher, Maruyama & Petersen, 1984) which we believe occur almost exclusively within the secretory cells (Wilson et al 1988;Bovell et al 1989 a). Genomic DNA from three of the patients was amplified by the polymerase chain reaction and the most common CF mutation identified by direct visualization following polyacrylamide gel electrophoresis (Rommens, Kerem, Greer, Chang, Tsui & Ray, 1990).…”

Electron Microbeam Analysis

“…Stimulation of human glands is principally by cholinergic activation and the formed sweat is a dilute solution mainly ofNaCI [95]. The species from which these results are taken represent physiologically different gland types.…”

“…Water was supplied ad libitum and sweat output was monitored [94,95]. Individuals were then put into a warm environment in a climatic chamber (40°C and 50% relative humidity).…”