Linked Life Data

238248

Source:http://linkedlifedata.com/resource/pubmed/id/238248

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
908
pubmed:dateCreated
1975-9-24
pubmed:abstractText
Pacemaker activity in atrial muscle and in Purkinje fibres is generated by a time-dependent decay of potassium current that allows the membrane to be depolarized to the threshold for action potential initiation. The kinetics of the pacemaker potassium currents in these two parts of the heart are sufficiently different to indicate that they correspond to different membrane structures. This conclusion is strengthened by the discovery that the mechanisms of acceleration produced by adrenaline are also quite different. In Purkinje fibres, the activation threshold for the potassium current is shifted in a depolarizing direction with no change in maximum amplitude. This voltage shift is adequate by itself to explain the acceleration. In atrial fibres the pacemaker potassium current is increased in amplitude with no shift in threshold. By itself, this action of adrenaline would slow pacemaker activity and the acceleration in this case is dependent on a large increase in the current attributable to calcium ions. The roles of cyclic 3',5'-AMP and of intracellular calcium ions in mediating the pacemaker actions of adrenaline will also be discussed.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0962-8436
pubmed:author
pubmed:issnType
Print
pubmed:day
10
pubmed:volume
270
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
527-37
pubmed:dateRevised
2009-10-27
pubmed:meshHeading
pubmed:year
1975
pubmed:articleTitle
Adrenergic control of cardian pacemaker currents.
pubmed:publicationType
Journal Article