The action of creatinol 0-phosphate on the inotropic effect of isoprenaline in isolated rat atria and in anesthetized dogs.
The action of N-methyl-N-(beta-hydroxyethyl) guanidine O-phosphate (creatinol O-phosphate) was studied on the contractility of the heart, in vitro on isolated rat atria and in vivo in anesthetized dogs. Creatinol O-phosphate was without action on the contractility of isolated rat atria stimulated by isoprenaline 10(-8) mol/l which produced the maximum inotropic effect. Creatinol O-phosphate increased the contractility evoked by isoprenaline 10(-5) mol/l and impaired the development of the negative inotropic effect evoked by prolonged treatment with this large dose. In dogs, creatinol O-phosphate pretreatment increased the positive inotropic effect of large but not low isoprenaline dosages. It is concluded that creatinol O-phosphate increased the contractile efficiency of the heart submitted to the action of an excess of catecholamines.
D000818:Animals; D003401:Creatine / Q000031:analogs & derivatives* / Q000494:pharmacology*; D004285:Dogs; D004347:Drug Interactions; D005260:Female; D006439:Hemodynamics / Q000187:drug effects; D066298:In Vitro Techniques; D007545:Isoproterenol / Q000494:pharmacology*; D009200:Myocardial Contraction / Q000187:drug effects*; D051381:Rats; D013997:Time Factors
C100173:creatinol phosphate; D007545:Isoproterenol; D003401:Creatine