Találati lista | Tudóstér

001-es BibID:	BIBFORM049387
Első szerző:	Almássy János (élettanász, biológus, angol-magyar szakfordító)
Cím:	Apical Ca2+-activated K+-channels in mouse parotid acinar cells / Janos Almassy, Ted Begenisich, David Yule
Dátum:	2012
ISSN:	0006-3495
Megjegyzések:	Ca2+ activation of Cl-- and K+-channels are key events underlying stimulated fluid secretion from parotid salivary glands. Cl--channels are exclusively present on the apical plasma membrane (PM) while the localization of K+-channels has not been established. Mathematical models have suggested that localization of some K+-channels to the apical PM is optimum for fluid secretion. A combination of whole cell electrophysiology and temporally resolved digital imaging with local manipulation of intracellular [Ca2+] was used to investigate if Ca2+-activated K+-channels are present in the apical PM of parotid acinar cells. Initial experiments established Ca2+ buffering conditions that produced brief, localized increases in [Ca2+] following focal laser photolysis of caged-Ca2+. Conditions were employed to isolate K+ and Cl- conductances. Photolysis at the apical PM resulted in a robust increase in K+ and Cl- currents. A localized reduction in [Ca2+] at the apical PM following photolysis of Diazo-2, a caged-Ca2+ chelator, resulted in a decrease in both K+ and Cl- currents. The K+ currents evoked by apical photolysis were partially blocked by both paxilline and TRAM-34, specific blockers of BK and IK respectively and almost abolished by incubation with both antagonists. Apical TRAM-34 sensitive K+ currents were also observed in BK null parotid acini. In contrast, when the [Ca2+] was increased at the basal PM no increase in either K+ or Cl- currents was evoked. These data provide strong evidence that K+- and Cl--channels are similarly distributed in the apical PM. Furthermore, both IK and BK channels are present in this domain and that the density of these channels appears higher in the apical vs. basal PM. In total, this study provides support for a model in which fluid secretion is optimized following expression of K+-channels specifically in the apical PM.
Tárgyszavak:	Természettudományok Biológiai tudományok idézhető absztrakt calcium release
Megjelenés:	Biophysical Journal. - 102 : 3 (2012), p. 650a-651a. -
További szerzők:	Begenisich, Ted B. Yule, David I.
Internet cím:	Szerző által megadott URL DOI Intézményi repozitóriumban (DEA) tárolt változat
Borító:
Saját polcon: