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Kinetics of P2X7 receptor-operated single channels currents.
Riedel T
,
Lozinsky I
,
Schmalzing G
,
Markwardt F
.
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Human P2X7 receptors were expressed in Xenopus laevis oocytes and single channels were recorded using the patch-clamp technique in the outside-out configuration. ATP4- evoked two types of P2X7 receptor-mediated single channel currents characterized by short-lived and long-lived openings. The short- and long-lasting open states had mean open times of approximately 5 and approximately 20 ms and slope conductances near -60 mV of 9 and 13 pS, respectively. The open probabilities of the short and long openings were strongly [ATP4-]-dependent with EC50 values of approximately 0.3 mM and approximately 0.1 mM ATP4-, respectively. The channel kinetics did not change significantly during sustained P2X7 receptor activation for several minutes, as was also observed in recordings in the cell-attached patch-clamp configuration. Activation and deactivation of the short openings followed exponential time courses with time constants in the range of 20 ms, and displayed a shallow [ATP4-] dependence of the activation process. The kinetics of the short channel openings at negative membrane potentials fitted well to a linear C-C-C-O model with two ATP4- binding steps at equal binding sites with a dissociation constant Kd of 139 microM.
Adinolfi,
Tyrosine phosphorylation of HSP90 within the P2X7 receptor complex negatively regulates P2X7 receptors.
2003, Pubmed
Adinolfi,
Tyrosine phosphorylation of HSP90 within the P2X7 receptor complex negatively regulates P2X7 receptors.
2003,
Pubmed
Auerbach,
Heterogeneous kinetic properties of acetylcholine receptor channels in Xenopus myocytes.
1986,
Pubmed
,
Xenbase
Boldt,
Glu496Ala polymorphism of human P2X7 receptor does not affect its electrophysiological phenotype.
2003,
Pubmed
,
Xenbase
Bretschneider,
Drug-dependent ion channel gating by application of concentration jumps using U-tube technique.
1999,
Pubmed
Bretschneider,
Nonselective cationic currents elicited by extracellular ATP in human B-lymphocytes.
1995,
Pubmed
Chessell,
Properties of the pore-forming P2X7 purinoceptor in mouse NTW8 microglial cells.
1997,
Pubmed
Colomar,
ATP stimulation of P2X(7) receptors activates three different ionic conductances on cultured mouse Schwann cells.
2001,
Pubmed
Colquhoun,
On the stochastic properties of single ion channels.
1981,
Pubmed
Colquhoun,
Fast events in single-channel currents activated by acetylcholine and its analogues at the frog muscle end-plate.
1985,
Pubmed
Colquhoun,
Relaxation and fluctuations of membrane currents that flow through drug-operated channels.
1977,
Pubmed
Ding,
Single channel properties of P2X2 purinoceptors.
1999,
Pubmed
,
Xenbase
Di Virgilio,
Nucleotide receptors: an emerging family of regulatory molecules in blood cells.
2001,
Pubmed
Di Virgilio,
The P2Z purinoceptor: an intriguing role in immunity, inflammation and cell death.
1995,
Pubmed
Faria,
Are second messengers crucial for opening the pore associated with P2X7 receptor?
2005,
Pubmed
Humphreys,
Isoquinolines as antagonists of the P2X7 nucleotide receptor: high selectivity for the human versus rat receptor homologues.
1998,
Pubmed
Jiang,
N-methyl-D-glucamine and propidium dyes utilize different permeation pathways at rat P2X(7) receptors.
2005,
Pubmed
Kim,
Proteomic and functional evidence for a P2X7 receptor signalling complex.
2001,
Pubmed
Klapperstück,
Characteristics of P2X7 receptors from human B lymphocytes expressed in Xenopus oocytes.
2000,
Pubmed
,
Xenbase
Klapperstück,
Functional evidence of distinct ATP activation sites at the human P2X(7) receptor.
2001,
Pubmed
,
Xenbase
Li,
Regulation of the P2X7 receptor permeability to large molecules by extracellular Cl- and Na+.
2005,
Pubmed
Magleby,
Modal gating of NMDA receptors.
2004,
Pubmed
Markwardt,
Gating of maxi K+ channels studied by Ca2+ concentration jumps in excised inside-out multi-channel patches (myocytes from guinea pig urinary bladder).
1992,
Pubmed
Markwardt,
Purinoceptor-operated cationic channels in human B lymphocytes.
1997,
Pubmed
Negulyaev,
Block by extracellular Mg2+ of single human purinergic P2X4 receptor channels expressed in human embryonic kidney cells.
2000,
Pubmed
North,
Molecular physiology of P2X receptors.
2002,
Pubmed
Nuttle,
Differential activation of cation channels and non-selective pores by macrophage P2z purinergic receptors expressed in Xenopus oocytes.
1994,
Pubmed
,
Xenbase
Nuttle,
Expression of the pore-forming P2Z purinoreceptor in Xenopus oocytes injected with poly(A)+ RNA from murine macrophages.
1993,
Pubmed
,
Xenbase
Petrou,
P2X7 purinoceptor expression in Xenopus oocytes is not sufficient to produce a pore-forming P2Z-like phenotype.
1997,
Pubmed
,
Xenbase
Rassendren,
The permeabilizing ATP receptor, P2X7. Cloning and expression of a human cDNA.
1997,
Pubmed
Schubert,
Multiple ligand-ion solutions: a guide for solution preparation and computer program understanding.
1996,
Pubmed
Sigworth,
Data transformations for improved display and fitting of single-channel dwell time histograms.
1987,
Pubmed
Smart,
P2X7 receptor cell surface expression and cytolytic pore formation are regulated by a distal C-terminal region.
2003,
Pubmed
,
Xenbase
Surprenant,
The cytolytic P2Z receptor for extracellular ATP identified as a P2X receptor (P2X7).
1996,
Pubmed
Ugur,
An ATP-gated cation channel with some P2Z-like characteristics in gastric smooth muscle cells of toad.
1997,
Pubmed
Virginio,
Effects of divalent cations, protons and calmidazolium at the rat P2X7 receptor.
1997,
Pubmed
Virginio,
Kinetics of cell lysis, dye uptake and permeability changes in cells expressing the rat P2X7 receptor.
1999,
Pubmed
Wilson,
Epithelial membrane proteins induce membrane blebbing and interact with the P2X7 receptor C terminus.
2002,
Pubmed
Zou,
Coupling of a P2Z-like purinoceptor to a fatty acid-activated K(+) channel in toad gastric smooth muscle cells.
2001,
Pubmed