title: Effect of praziquantel on the cardiotonic action of cardiac glycosides.
abstract: The effect of praziquantel on isolated left guinea-pig atria has been studied. Praziquantel caused a concentration-dependent increase in the force of contraction of the isolated left atria, an effect which may be due to an increase in Ca++ fluxes. Praziquantel antagonized the cardiotonic effect of cardiac glycosides on guinea-pig atria. This antagonism is neither due to an alteration of Ca++ concentration in the cell, nor to a direct action on Na+, K+-ATPase, nor to inhibition of the binding of cardiac glycosides to heart tissue. This interaction may involve an enhancement of K+ fluxes in cardiac cells under the influence of praziquantel.
mesh_terms: D000818:Animals; D002301:Cardiac Glycosides / Q000037:antagonists & inhibitors / Q000378:metabolism / Q000494:pharmacology*; D006168:Guinea Pigs; D006325:Heart Atria / Q000187:drug effects; D007473:Ion Channels / Q000187:drug effects; D008297:Male; D009200:Myocardial Contraction / Q000187:drug effects*; D011188:Potassium / Q000378:metabolism; D011223:Praziquantel / Q000494:pharmacology*; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism
chemical_list: D002301:Cardiac Glycosides; D007473:Ion Channels; D011223:Praziquantel; D000254:Sodium-Potassium-Exchanging ATPase; D011188:Potassium