title: [Effects of ruthenium red on the kinetics of potassium loss and on the calcium levels of the rat heart, perfused with potassium-free solutions].
abstract: In the presence of ruthenium red (R.R.) (0.1 and 1 mM), the kinetics of K losses during K-free perfusion of Langendorff perfused rat hearts is modified and the Ca overload produced by K-free perfusion is reduced by 40%. R.R. enhances the K loss rate increase which is Ca-dependent (the "hump") whereas it reduces the K loss rates in the phase preceding the "hump" and the K loss rates during Ca-free perfusions. The first effect can be considered as evidence in favor of a cytoplasmic Ca increase resulting from the inhibition by R.R. of Ca sequestration by mitochondria; the second as well as the reduced Ca overload seem due to a reduction by R.R. of the membrane permeability.
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002463:Cell Membrane Permeability / Q000187:drug effects; D007700:Kinetics; D009206:Myocardium / Q000378:metabolism*; D010477:Perfusion; D011188:Potassium / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D012428:Ruthenium / Q000494:pharmacology*; D012430:Ruthenium Red / Q000494:pharmacology*
chemical_list: D012430:Ruthenium Red; D012428:Ruthenium; D011188:Potassium; D002118:Calcium
vernacular_title: Effets du rouge de ruthénium sur la cinétique des pertes de potassium et sur les teneurs en calcium du coeur de rat, perfusé par des solutions dépourvues de potassium.