Bisphenol A inhibits Cl(-) secretion by inhibition of basolateral K+ conductance in human airway epithelial cells

J Pharmacol Exp Ther. 2002 Jul;302(1):80-7. doi: 10.1124/jpet.302.1.80.

Abstract

There has been growing concern about the potential threat of hormone-disrupting chemicals like bisphenol A to various aspects of animal and human health. We studied the effects of bisphenol A on the Cl(-) secretion in human airway epithelial Calu-3 cells. Pretreatment with bisphenol A (IC(50) = 60 microM, for 30 min) prevented isoproterenol (10 nM)-generated short-circuit current (I(sc)) more potently than 17beta-estradiol or tamoxifen (IC(50) = 1 mM). 5'-Nitro-2-(3-phenylpropylamino) benzoate-sensitive apical conductance potentiated by isoproterenol was not affected by the pretreatment with either of these estrogenic compounds. The effects of bisphenol A were simulated in I(sc) responses to forskolin (10 microM) and 8-bromo-cAMP (1 mM). Nystatin permeabilization of Calu-3 monolayers revealed that bisphenol A attenuated 8-bromo-cAMP-induced basolateral K+ current, which is sensitive to clotrimazole (30 microM) and insensitive to charybdotoxin (100 nM), without affecting the apical Cl(-) current. Bisphenol A, but neither 17beta-estradiol nor tamoxifen, interrupted the charybdotoxin-sensitive component of I(sc) stimulated by 1-ethyl-2-benzimidazolinone (1-EBIO; 500 microM). The inhibitory effects of bisphenol A on these Cl(-) secretory stimuli were remarkable when applied to the apical rather than the basolateral membrane. Alternatively, long-term incubation of bisphenol A (1 microM; 12-72 h) had no discernible effect on isoproterenol- and 1-EBIO-induced Cl(-) secretion. These findings indicate that short-term exposure to bisphenol A attenuates transepithelial Cl(-) secretion through inhibition of both cAMP- and Ca(2+)-activated K+ channels on the basolateral membrane, interacting from the cytosolic surface in Calu-3 cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adrenergic beta-Agonists / pharmacology
  • Benzhydryl Compounds
  • Benzimidazoles / pharmacology
  • Cell Line
  • Chloride Channel Agonists
  • Chloride Channels / drug effects
  • Chlorides / metabolism*
  • Cyclic AMP / physiology
  • Cystic Fibrosis Transmembrane Conductance Regulator / biosynthesis
  • Down-Regulation / drug effects
  • Electrophysiology
  • Epithelial Cells / drug effects
  • Epithelial Cells / metabolism*
  • Humans
  • Isoproterenol / pharmacology
  • Phenols / pharmacology*
  • Phenotype
  • Potassium Channel Blockers*
  • Potassium Channels / agonists
  • Respiratory System / cytology
  • Respiratory System / drug effects
  • Respiratory System / metabolism

Substances

  • Adrenergic beta-Agonists
  • Benzhydryl Compounds
  • Benzimidazoles
  • CFTR protein, human
  • Chloride Channel Agonists
  • Chloride Channels
  • Chlorides
  • Phenols
  • Potassium Channel Blockers
  • Potassium Channels
  • Cystic Fibrosis Transmembrane Conductance Regulator
  • Cyclic AMP
  • Isoproterenol
  • 1-ethyl-2-benzimidazolinone
  • bisphenol A