Permeabilization via the P2X(7) purinoreceptor reveals the presence of a Ca2+-activated Cl- conductance in the apical membrane of murine tracheal epithelial cells
Gabriel, SE; Makhlina, M; Martsen, E; Thomas, EJ; Lethem, MI; Boucher, RC
HERO ID
2789349
Reference Type
Journal Article
Year
2000
Language
English
PMID
| HERO ID | 2789349 |
|---|---|
| In Press | No |
| Year | 2000 |
| Title | Permeabilization via the P2X(7) purinoreceptor reveals the presence of a Ca2+-activated Cl- conductance in the apical membrane of murine tracheal epithelial cells |
| Authors | Gabriel, SE; Makhlina, M; Martsen, E; Thomas, EJ; Lethem, MI; Boucher, RC |
| Journal | Journal of Biological Chemistry |
| Volume | 275 |
| Issue | 45 |
| Page Numbers | 35028-35033 |
| Abstract | Calcium-activated Cl(-) secretion is an important modulator of regulated ion transport in murine airway epithelium and is mediated by an unidentified Ca(2+)-stimulated Cl(-) channel. We have transfected immortalized murine tracheal epithelial cells with the cDNA encoding the permeabilizing P2X(7) purinoreceptor (P2X(7)-R) to selectively permeabilize the basolateral membrane and thereby isolate the apical membrane Ca(2+)-activated Cl(-) current. In P2X(7)-R-permeabilized cells, we have demonstrated that UTP stimulates a Cl(-) current across the apical membrane of CF and normal murine tracheal epithelial cells. The magnitude of the UTP-stimulated current was significantly greater in CF than in normal cells. Ion substitution studies demonstrated that the current exhibited a permselectivity sequence of Cl(-) > I(-) > Br(-) > gluconate(-). We have also determined a rank order of potency for putative Cl(-) channel blockers: niflumic acid > or = 5-nitro-2-(3-phenylpropylamino)benzoic acid > 4, 4'-diisothiocyanostilbene-2,2'-disulfonate > glybenclamide > diphenlyamine-2-carboxylate, tamoxifen, and p-tetra-sulfonato-tetra-methoxy-calix[4]arene. Complete characterization of this current and the corresponding single channel properties could lead to the development of a new therapy to correct the defective airway surface liquid in cystic fibrosis patients. |
| Doi | 10.1074/jbc.M004953200 |
| Pmid | 10944530 |
| Wosid | WOS:000165422800029 |
| Is Certified Translation | No |
| Dupe Override | No |
| Is Public | Yes |
| Language Text | English |