title: CFTR-mediated Cl(-) transport in the acinar and duct cells of rabbit lacrimal gland.
abstract: OBJECTIVE
  We investigated the role that the cystic fibrosis transmembrane conductance regulator (CFTR) may play in Cl(-) transport in the acinar and ductal epithelial cells of rabbit lacrimal gland (LG).
  
  
  METHODS
  Primary cultured LG acinar cells were processed for whole-cell patch-clamp electrophysiological recording of Cl(-) currents by using perfusion media with high and low [Cl(-)], 10 µM forskolin and 100 µM 3-isobutyl-1-methylxanthine (IBMX), the non-specific Cl(-) channel blocker 4,4'-disothiocyanostilbene-2, 2' sulphonic acid (DIDS; 100 µM) and CFTRinh-172 (10 µM), a specific blocker for CFTR. Ex vivo live cell imaging of [Cl(-)] changes in duct cells was performed on freshly dissected LG duct with a multiphoton confocal laser scanning microscope using a Cl(-) sensitive fluorescence dye, N-[ethoxycarbonylmethyl]-6-methoxy-quinolinium bromide.
  
  
  RESULTS
  Whole-cell patch-clamp studies demonstrated the presence of Cl(-) current in isolated acinar cells and revealed that this Cl(-) current was mediated by CFTR channel. Live cell imaging also showed the presence of CFTR-mediated Cl(-) transport across the plasma membrane of duct cells.
  
  
  CONCLUSIONS
  Our previous data showed the presence of CFTR in all acinar and duct cells within the rabbit LG, with expression most prominent in the apical membranes of duct cells. The present study demonstrates that CFTR is actively involved in Cl(-) transport in both acinar cells and epithelial cells from duct segments, suggesting that CFTR may play a significant role in LG secretion.
authors.affiliation: Department of Cell and Neurobiology, Doheny Eye Institute, University of Southern California, Los Angeles, CA 90089-9112, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Lu
authors.forename: Chuanqing
authors.initials: C
authors.lastname: Ding
mesh_terms: D015056:1-Methyl-3-isobutylxanthine / Q000494:pharmacology; D017878:4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid / Q000494:pharmacology; D061354:Acinar Cells / Q000378:metabolism*; D000818:Animals; D001565:Benzoates / Q000494:pharmacology; D001692:Biological Transport; D002478:Cells, Cultured; D018118:Chloride Channels / Q000037:antagonists & inhibitors / Q000378:metabolism*; D002712:Chlorides / Q000378:metabolism*; D005576:Colforsin / Q000494:pharmacology; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000037:antagonists & inhibitors / Q000502:physiology*; D004847:Epithelial Cells / Q000378:metabolism*; D005260:Female; D005456:Fluorescent Dyes; D007765:Lacrimal Apparatus / Q000166:cytology / Q000378:metabolism*; D018613:Microscopy, Confocal; D018408:Patch-Clamp Techniques; D010726:Phosphodiesterase Inhibitors / Q000494:pharmacology; D011817:Rabbits; D053778:Thiazolidines / Q000494:pharmacology
chemical_list: C482900:3-((3-trifluoromethyl)phenyl)-5-((3-carboxyphenyl)methylene)-2-thioxo-4-thiazolidinone; D001565:Benzoates; D018118:Chloride Channels; D002712:Chlorides; D005456:Fluorescent Dyes; D010726:Phosphodiesterase Inhibitors; D053778:Thiazolidines; D019005:Cystic Fibrosis Transmembrane Conductance Regulator; D005576:Colforsin; D017878:4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid; D015056:1-Methyl-3-isobutylxanthine