Linked Life Data

2158404

Source:http://linkedlifedata.com/resource/pubmed/id/2158404

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1990-5-29
pubmed:abstractText
1. Standard microelectrode techniques were used to record intracellular action potentials from guinea-pig ventricular myocardium superfused with either control physiological saline (pH 7.5; pO2 500 mmHg; [K+] 5.6 mmol/L) or 'simulated ischaemic' solution (pH 6.4; pO2 90 mmHg; [K+] 11.2 mmol/L). 2. The effects on action potential parameters of therapeutic concentrations of lignocaine, amiodarone and encainide were studied under both conditions. 3. Simulated ischaemia, in the absence of drugs, produced marked reductions in resting potential (-86.6 +/- 2.3 to -64.7 +/- 3.5 mV), maximum rate of depolarization (Vmax; 263 +/- 66 to 106 +/- 36 V/s) and action potential duration (164 +/- 24 to 97 +/- 26 ms). No drug produced any additional effect on resting potential. 4. All three drugs produced enhanced depression of Vmax in ischaemia compared to control conditions (class I effect). This was much more marked for lignocaine and amiodarone (inactivated channel blockers) than for encainide (open channel blocker). 5. In addition the prolongation of action potential duration seen with acute exposure to amiodarone (174 +/- 12 to 192 +/- 17 ms; class III effect) was abolished under simulated ischaemic conditions. 6. It is concluded that lignocaine and amiodarone exert greater selectivity for ischaemic tissue than does encainide and that amiodarone may function primarily as a class I agent under ischaemic conditions.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0305-1870
pubmed:author
pubmed:issnType
Print
pubmed:volume
17
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
135-45
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Selective depression of maximum rate of depolarization of guinea-pig ventricular action potentials by amiodarone and lignocaine in simulated ischaemia: comparison with encainide.
pubmed:affiliation
School of Physiology and Pharmacology, University of NSW, Kensington, Australia.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't