Nucleotide-evoked ion transport and [Ca2+]i changes in normal and hyperhidrotic human sweat gland cells

Apical and basolateral application of ATP and UTP evoked [Ca2+](i) and short circuit current (Isc) increases in normal and hyperhidrotic human eccrine sweat gland cells grown into functionally polarised epithelia on permeable supports. Basolateral application to hyperhidrotic cells exhibited a markedly greater increase in Ise than in normal cells. Hyperhidrotic cells also demonstrated differences from the normal in [Ca2+](i) and Isc responses to ATP when pre-treated with thapsigargin. The data demonstrate the presence of apical and basolateral receptors that allow nucleotides to increase [Ca2+](i) and Isc. The results suggest that changes from the normal in transepithelial ion transport contribute to the characteristic excessive fluid production of hyperhidrotic sweat glands. (C) 2000 Elsevier Science B.V. All rights reserved.