title: Cardiotonic action of ring A-modified cardenolides, with special reference to cleavage of the ring.
mesh_terms: D000818:Animals; D001001:Anura; D002298:Cardenolides / Q000494:pharmacology*; D004073:Digitoxigenin / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D006168:Guinea Pigs; D006321:Heart / Q000187:drug effects; D006325:Heart Atria / Q000187:drug effects; D066298:In Vitro Techniques; D009200:Myocardial Contraction / Q000187:drug effects*; D011188:Potassium / Q000494:pharmacology; D013268:Stimulation, Chemical; D013329:Structure-Activity Relationship
chemical_list: D002298:Cardenolides; D004073:Digitoxigenin; D011188:Potassium