title: Inhibition of anion channels derived from mitochondrial membranes of the rat heart by stilbene disulfonate--DIDS.
abstract: The objective of this work was to characterize in more detail the inhibition effect of diisothiocyanatostilbene-2',2-disulfonic acid (DIDS) on anion channels isolated from the rat heart mitochondria. The channels reconstituted into a planar lipid membrane displayed limited powers of discrimination between anions and cations and the ion conductance measured under asymmetric (250/50 mM KCl, cis/trans) and symmetric (150 mM KCl) conditions was approximately 100 pS. DIDS caused a dramatic decrease in the channel activity (IC(50) = 11.7 +/- 3.1 microM) only when it was added to the cis side of a planar lipid membrane. The inhibition was accompanied by the significant prolongation of closings and the shortening of openings within the burst as well as gaps between bursts were prolonged and durations of bursts were reduced. The blockade was complete and irreversible when concentration of DIDS was increased up to 200 microM. Our data indicate that DIDS is an allosteric blocker of mitochondrial anion channels and this specific effect could be used as a tool for reliable identification of anion channels on the functional level.
authors: Institute of Molecular Physiology and Genetics, Slovak Academy of Sciences, Vlarska 5, 83334 Bratislava, Slovak Republic.
authors: Zuzana
authors: Z
authors: Tomaskova
authors: Jana
authors: J
authors: Gaburjakova
authors: Anna
authors: A
authors: Brezova
authors: Marta
authors: M
authors: Gaburjakova
mesh_terms: D017878:4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid / Q000494:pharmacology*; D000818:Animals; D004594:Electrophysiology; D066298:In Vitro Techniques; D007473:Ion Channels / Q000037:antagonists & inhibitors*; D007700:Kinetics; D008051:Lipid Bilayers; D008929:Mitochondria, Heart / Q000187:drug effects* / Q000378:metabolism*; D051381:Rats; D013367:Submitochondrial Particles / Q000187:drug effects / Q000378:metabolism
chemical_list: D007473:Ion Channels; D008051:Lipid Bilayers; D017878:4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid