Abstract:
:Open channel properties of canine cardiac Purkinje cell Na+ channels were studied with single channel cell-attached recording and with whole cell macroscopic current recording in internally perfused cells. Single channel currents and membrane currents increased with an increase in Na+ concentration, but showed evidence of saturation. Assuming first-order binding, the Km for Na+ was 370 mM. PCs/PNa was 0.020 and PK/PNa was 0.094. The current-voltage relationship for single channels showed prominent flattening in the hyperpolarizing direction. This flattening was accentuated by 10 mM Ca2+ and was greatly reduced in O mM Ca2+, indicating that the rectification was a consequence of Ca2+ block of the Na+ channels. A similar instantaneous current-voltage relationship was seen for the whole cell membrane currents. These results demonstrate that the cardiac channel shows substantial Ca2+ block, although it is relatively insensitive to tetrodotoxin. The Na+ and Ca2+ binding properties could be modeled by the four-barrier Eyring rate theory model, with similar values to those reported for the neuroblastoma Na+ channel (Yamamoto, D.,J.Z. Yeh, and T. Narahashi, 1984, Biophys J., 45:337-344).
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Sheets MF,Scanley BE,Hanck DA,Makielski JC,Fozzard HAdoi
10.1016/S0006-3495(87)83183-1subject
Has Abstractpub_date
1987-07-01 00:00:00pages
13-22issue
1eissn
0006-3495issn
1542-0086pii
S0006-3495(87)83183-1journal_volume
52pub_type
杂志文章abstract::A subsarcolemmal tubular system network (SSTN) has been detected in skeletal muscle fibers by confocal imaging after the removal of the sarcolemma. Here we confirm the existence and resolve the fine architecture and the localization of the SSTN at an unprecedented level of detail by examining extracellularly applied t...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2013.04.029
更新日期:2013-06-04 00:00:00
abstract::In recent in vitro experiments, it has been demonstrated that the 47-kDa fragment of the talin molecule and the 32-kDa fragment of the vinculin molecule interact with acidic phospholipids. By using a computer analysis method, we determined the hydrophobic and amphipathic stretches of these fragments and, by applying a...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(95)79894-0
更新日期:1995-07-01 00:00:00
abstract::We examined four cardiomyopathy-causing mutations of troponin I that appear to disturb function by altering the distribution of thin filament states. The R193H (mouse) troponin I mutant had greater than normal actin-activated myosin-S1 ATPase activity in both the presence and absence of calcium. The rate of ATPase act...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2008.12.3909
更新日期:2009-03-18 00:00:00
abstract::We present higher-order moment analysis of fluorescence intensity fluctuations from individual laser scanning microscopy images applied to study monomer-oligomer distributions. We demonstrate that the number densities and brightness ratios of a mixed population of monomers and oligomers can be determined by analyzing ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.106.091181
更新日期:2006-11-15 00:00:00
abstract::Plasmodium falciparum malaria-infected red blood cells (IRBCs), or erythrocytes, avoid splenic clearance by adhering to host endothelium. Upregulation of endothelial receptors intercellular adhesion molecule-1 (ICAM-1) and cluster of differentiation 36 (CD36) are associated with severe disease pathology. Most in vitro...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2019.11.016
更新日期:2020-01-07 00:00:00
abstract::Despite growing interest in light-driven ion pumps for use in optogenetics, current estimates of their transport rates span two orders of magnitude due to challenges in measuring slow transport processes and determining protein concentration and/or orientation in membranes in vitro. In this study, we report, to our kn...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2018.06.009
更新日期:2018-07-17 00:00:00
abstract::A detailed experimental description of molecular dynamics requires an accurate description of the global correlation time. For the gramicidin cation-selective channel the local dynamics of the polypeptide backbone are thought to play a very significant role in the functional process of this channel which occurs on the...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(93)81150-0
更新日期:1993-09-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.107.115220
更新日期:2008-03-01 00:00:00
abstract::This paper describes a new technique that can be used to study chloroplast volume regulation in vivo. Nuclear magnetic resonance spectroscopy was used to measure relative amounts of chloroplast water in Acer platanoides leaves as they dried in air, and also in leaf disks exposed to aqueous polyethylene glycol, sucrose...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(92)81930-6
更新日期:1992-05-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(85)83952-7
更新日期:1985-04-01 00:00:00
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pub_type: 杂志文章
doi:10.1016/j.bpj.2013.12.008
更新日期:2014-01-21 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2013.03.051
更新日期:2013-05-07 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(89)82883-8
更新日期:1989-05-01 00:00:00
abstract::Theoretical studies of the electronic structure and spectra of models for the ferric resting state and Compound I intermediates of horseradish peroxidase (HRP-I) and catalase (CAT-I) have been performed using the INDO-RHF/CI method. The goals of these studies were twofold: i) to determine whether the axial ligand of H...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(95)80160-8
更新日期:1995-01-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.105.067223
更新日期:2005-11-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(85)83760-7
更新日期:1985-07-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(72)86106-X
更新日期:1972-06-01 00:00:00
abstract::A simulation of the function of the human heart and heart muscle has been developed in the form of a digital computer code. For a given set of values for the input variables, realistic values of the cardiac output variables are predicted. A detailed discussion of the simulation and some results obtained from its appli...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(73)86011-4
更新日期:1973-07-01 00:00:00
abstract::Guanidinium and acetamidinium, when added to the bathing solution in concentrations of approximately 0.1M, cause brief blocks in the single channel potassium currents from channels formed in planar lipid bilayers by gramicidin A. Single channel lifetimes are not affected indicating that the channel structure is not mo...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(91)82303-7
更新日期:1991-04-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.107.118802
更新日期:2008-02-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2010.07.053
更新日期:2010-10-06 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(92)81583-7
更新日期:1992-07-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(00)76820-2
更新日期:2000-06-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.108.132175
更新日期:2008-09-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
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更新日期:1998-12-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
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更新日期:1993-04-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2017.08.018
更新日期:2017-10-03 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.107.125369
更新日期:2009-02-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
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更新日期:1993-07-01 00:00:00
abstract::A new experimental approach has been developed to study the distribution of local electrostatic potential around specific protons in biologically important molecules. The approach is the development of a method denoted as "spin label/spin probe," which was proposed by one of us (. Mol. Biol. 6:498-507). The proposed m...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(99)76902-X
更新日期:1999-07-01 00:00:00