Abstract:
:A model for the Na-K exchange pump was applied to data on Na(+)-loaded frog sartorius muscle, and was used to relate the rate of adenosine triphosphate (ATP) hydrolysis to the electrical properties of the cell membrane. Membrane hyperpolarization was considered to arise from an electrical current which was produced by the hydrolysis reaction coupled to ion movements, and which flowed across the membrane. The reaction rate, as calculated from hyperpolarization, agreed with direct measurements of ATP hydrolysis and with the rate estimated from Na(+) tracer efflux studies. Although Na(+) is actively extruded, the model showed that K(+) is inwardly transported if the potassium permeability of the membrane is less than about 6.6 x 10(-6) cm/sec, as is suggested by resistance data. Calculations indicated that the reaction conductance L(rr) was relatively constant when compared with the reaction rate and reaction free energy for large changes in internal and external ionic concentrations. Its value agreed with the value obtained from the dependence of Na(+) tracer efflux on external K(+). A set of experiments was suggested which would provide a more complete interpretation of the data.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Rapoport SIdoi
10.1016/S0006-3495(71)86243-4subject
Has Abstractpub_date
1971-08-01 00:00:00pages
631-47issue
8eissn
0006-3495issn
1542-0086pii
S0006-3495(71)86243-4journal_volume
11pub_type
杂志文章abstract::The wide use of lattice-sum strategies in biomolecular simulations has raised many questions on potential artifacts in these strategies. One interesting question is the artifacts in the counterion distributions of highly charged systems. As one would anticipate, Coulombic interactions under the periodic boundary condi...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2009.05.012
更新日期:2009-07-22 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(01)75801-8
更新日期:2001-09-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.106.095547
更新日期:2007-05-15 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2018.08.011
更新日期:2018-09-18 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(68)86493-8
更新日期:1968-03-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(01)75910-3
更新日期:2001-11-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(99)77205-X
更新日期:1999-01-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2009.04.014
更新日期:2009-06-17 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2018.09.009
更新日期:2018-11-06 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:2001-08-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2011.08.055
更新日期:2011-10-19 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.105.072942
更新日期:2006-03-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.105.063263
更新日期:2005-08-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2011.09.055
更新日期:2011-11-16 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2016.11.3208
更新日期:2017-02-07 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(97)78851-9
更新日期:1997-05-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(98)77741-0
更新日期:1998-12-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.104.049031
更新日期:2004-12-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(90)82556-X
更新日期:1990-03-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.107.112698
更新日期:2007-11-15 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.104.043059
更新日期:2004-10-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.104.040576
更新日期:2004-07-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2015.09.018
更新日期:2015-11-03 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(02)75561-6
更新日期:2002-04-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.106.083816
更新日期:2006-08-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(75)85881-4
更新日期:1975-10-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.107.104562
更新日期:2007-10-15 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(92)81893-3
更新日期:1992-04-01 00:00:00
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journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2020.08.028
更新日期:2020-10-06 00:00:00
abstract::A microscopic model of passive transverse mass transport of small solutes in the viable epidermal layer of human skin is formulated on the basis of a hexagonal array of cells (i.e., keratinocytes) bounded by 4-nm-thick, anisotropic lipid bilayers and separated by 1-μm layers of extracellular fluid. Gap junctions and t...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2013.03.056
更新日期:2013-05-21 00:00:00