Linked Life Data

2454451

Source:http://linkedlifedata.com/resource/pubmed/id/2454451

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1988-7-21
pubmed:abstractText
The effects of monovalent internal cations Cs+, Li+ and Na+ on potassium channel conductance in the frog node of Ranvier were studied by means of the voltage clamp. As previously reported, when 10-80% of the internal K+ was replaced by one of the above cations, the steady-state current-voltage relationship was significantly modified. The main effect was a voltage-dependent attenuation of the currents. We demonstrate that the current attenuation is associated with a change in the channel gating kinetics. For small depolarizations the kinetics can be described by the usual potassium conductance activation time constant, tau n. However, under certain experimental conditions (e.g. substitution of the intracellular K+ with 10% Cs+), during larger depolarizations, stepping the membrane potential to values above 40-60 mV, the conductance develops with two time constants: tau n and a new, slower time constant that, in contrast to tau n, grows with membrane potential. These results can be explained by assuming that the cations may occupy two different sites in the channel; when the first site is occupied the channel is blocked, while occupation of the second site results in slowing of the gating kinetics in the affected channels.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0031-6768
pubmed:author
pubmed:issnType
Print
pubmed:volume
411
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
312-5
pubmed:dateRevised
2003-11-14
pubmed:meshHeading
pubmed:year
1988
pubmed:articleTitle
Effect of Cs+, Li+ and Na+ on the potassium conductance and gating kinetics in the frog node of Ranvier.
pubmed:affiliation
Rappaport Family Institute for Research in the Medical Sciences, Technion-Israel Institute of Technology, Haifa, Israel.
pubmed:publicationType
Journal Article