Is PGI2 arrhythmogenic? Investigations on ouabain induced arrhythmias in cats.
The present study investigated the effect of PGI2 on ouabain induced arrhythmias in cats. PGI2 was infused at a dose of 1.0, 2.0 and 5.0 microgram/kg . min. PGI2 in a dose of 1.0 microgram/kg . min was without any antiarrhythmic effect. Infusions of 2.0 and 5.0 microgram/kg . min PGI2 in 3 of 10 and 7 of 10 animals, respectively, converted the ouabain induced arrhythmias into a sinus rhythm. The duration of the antiarrhythmic effect after infusion of 2.0 microgram/kg . min lasted about 21 min, whereas the higher dose (5.0 microgram/kg . min) had a shorter effect (about 2 min). Under these conditions and doses the systolic blood pressure decreased between 35% and 39% and the diastolic blood pressure was reduced by about 50%. Thus PGI2 showed when used in the given dose range, an antiarrhythmic effect on ouabain induced arrhythmias in cats. The importance of dosage, methods and species is here discussed.
D000818:Animals; D001145:Arrhythmias, Cardiac / Q000139:chemically induced*; D001794:Blood Pressure / Q000187:drug effects; D002415:Cats; D004305:Dose-Response Relationship, Drug; D011464:Epoprostenol / Q000494:pharmacology*; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D008297:Male; D010042:Ouabain / Q000494:pharmacology*; D011453:Prostaglandins / Q000494:pharmacology*
D011453:Prostaglandins; D010042:Ouabain; D011464:Epoprostenol