HOME HELP CONTACT US SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Pearson, J. Articles by Mauchamp, J. Search for Related Content PubMed PubMed Citation Articles by Pearson, J. Articles by Mauchamp, J.

Confluent monolayers of cultured porcine thyroid cells transport fluid from the apical to the basal surface, forming circumscribed zones of detachment from the culture dish substrate (domes). The transepithelial potential (TEP), positive on the basal side, was 12·9 ± 0·4 (S.E.M.) mV (n = 93) under control conditions, increasing to 38·9 ± 0·3 mV (n = 281) when fluid transport was stimulated by prostaglandin E₂ (PGE₂; 1 µmol/l). Forskolin (1 µmol/l) and 8-(4-chlorophenylthio) adenosine 3',5'-cyclic monophosphate (0·5 mmol/l) were also effective in increasing TEP. Addition of amiloride in concentrations sufficient to block fluid transport (100 µmol/l) reduced the TEP to 5·8 ± 0·3 mV (n=76). Substitution of N-methyl-D-glucamine for sodium in the medium reduced the PGE₂-stimulated TEP to 13·4 ± 0·8 mV (n = 32). Substitution of gluconate for chloride increased the TEP to 40·3 ± 0·4 mV (n = 160). Removal of bicarbonate or potassium from the medium, or addition of ouabain (200 µmol/l) were also effective in reducing the TEP. In media of low bicarbonate concentration (1 mmol NaHCO₃/l), acetazolamide (1 mmol/l) reduced the TEP. Fluid transport by the monolayer as measured by the change in height of domes was increased by PGE₂ (1 µmol/l). PGE₂-stimulated fluid transport was inhibited by sodium or chloride ion substitution, bicarbonate removal or the addition of ouabain (200 µmol/l) or amiloride (100 µmol/l). It was concluded that fluid transport in thyroid monolayers is mediated by rheogenic sodium transport with chloride transport being passive, electrogenically coupled to sodium transport. Sodium entry to the apical pole of the cells occurs by an amiloride-sensitive mechanism, and sodium extrusion at the basal pole depends on the Na⁺/K⁺ ATPase.

J. Endocr. (1988) 119, 309–314

This article has been cited by other articles:

				A. Yoshida, I. Hisatome, S. Taniguchi, N. Sasaki, Y. Yamamoto, J. Miake, H. Fukui, H. Shimizu, T. Okamura, T. Okura, et al. Mechanism of Iodide/Chloride Exchange by Pendrin Endocrinology, September 1, 2004; 145(9): 4301 - 4308. [Abstract] [Full Text] [PDF]