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Blockade of the CFTR chloride channel by glibenclamide was studied in Xenopus oocytes using two-electrode voltage-clamp recordings, macropatch recordings, and summations of single-channel currents, in order to test a kinetic model recently developed by us from single-channel experiments. Both the forward and reverse macroscopic reactions, at negative and positive membrane potential V(M), respectively, were slow in comparison to those reactions for other CFTR pore blockers such as DPC and NPPB, resulting in prominent relaxations on the order of tens of milliseconds. The rate of the reverse reaction was voltage-dependent, and dependent on the Cl(-) driving force, while that of the forward reaction was not. In inside-out macropatches, block and relief from block occurred in two distinct phases that differed in apparent affinity. The results are consistent with the presence of multiple glibenclamide binding sites in CFTR, with varying affinity and voltage dependence; they support the kinetic model and suggest experimental approaches for identification of those sites by mutagenesis.
al-Awqati,
Regulation of ion channels by ABC transporters that secrete ATP.
1995, Pubmed
al-Awqati,
Regulation of ion channels by ABC transporters that secrete ATP.
1995,
Pubmed
Cai,
Inhibition of heterologously expressed cystic fibrosis transmembrane conductance regulator Cl- channels by non-sulphonylurea hypoglycaemic agents.
1999,
Pubmed
Goldstein,
Site-specific mutations in a minimal voltage-dependent K+ channel alter ion selectivity and open-channel block.
1991,
Pubmed
,
Xenbase
Golstein,
P-glycoprotein inhibition by glibenclamide and related compounds.
1999,
Pubmed
Gupta,
Point mutations in the pore region directly or indirectly affect glibenclamide block of the CFTR chloride channel.
2002,
Pubmed
Hanrahan,
Inhibition of an outwardly rectifying anion channel by HEPES and related buffers.
1990,
Pubmed
Haws,
CFTR channels in immortalized human airway cells.
1992,
Pubmed
Ishihara,
Block by MOPS reveals a conformation change in the CFTR pore produced by ATP hydrolysis.
1997,
Pubmed
Linsdell,
Disulphonic stilbene block of cystic fibrosis transmembrane conductance regulator Cl- channels expressed in a mammalian cell line and its regulation by a critical pore residue.
1996,
Pubmed
Mathews,
Dibasic protein kinase A sites regulate bursting rate and nucleotide sensitivity of the cystic fibrosis transmembrane conductance regulator chloride channel.
1998,
Pubmed
McCarty,
Voltage-dependent block of the cystic fibrosis transmembrane conductance regulator Cl- channel by two closely related arylaminobenzoates.
1993,
Pubmed
,
Xenbase
McCarty,
Permeation through the CFTR chloride channel.
2000,
Pubmed
McDonough,
Novel pore-lining residues in CFTR that govern permeation and open-channel block.
1994,
Pubmed
Neher,
Local anaesthetics transiently block currents through single acetylcholine-receptor channels.
1978,
Pubmed
Quick,
Incubation with horse serum increases viability and decreases background neurotransmitter uptake in Xenopus oocytes.
1992,
Pubmed
,
Xenbase
Riordan,
Identification of the cystic fibrosis gene: cloning and characterization of complementary DNA.
1989,
Pubmed
Schultz,
Glibenclamide blockade of CFTR chloride channels.
1996,
Pubmed
Sheppard,
Mechanism of glibenclamide inhibition of cystic fibrosis transmembrane conductance regulator Cl- channels expressed in a murine cell line.
1997,
Pubmed
Walsh,
Structural and ionic determinants of 5-nitro-2-(3-phenylprophyl-amino)-benzoic acid block of the CFTR chloride channel.
1999,
Pubmed
,
Xenbase
Winter,
Effect of ATP concentration on CFTR Cl- channels: a kinetic analysis of channel regulation.
1994,
Pubmed
Zhang,
Steady-state interactions of glibenclamide with CFTR: evidence for multiple sites in the pore.
2004,
Pubmed
,
Xenbase
Zhang,
Interaction between permeation and gating in a putative pore domain mutant in the cystic fibrosis transmembrane conductance regulator.
2000,
Pubmed
,
Xenbase
Zhang,
Direct comparison of NPPB and DPC as probes of CFTR expressed in Xenopus oocytes.
2000,
Pubmed
,
Xenbase
Zhang,
Voltage-sensitive gating induced by a mutation in the fifth transmembrane domain of CFTR.
2002,
Pubmed
,
Xenbase
Zhou,
Probing an open CFTR pore with organic anion blockers.
2002,
Pubmed