The influence of prostaglandins E1 and E2 on ouabain cardiotoxicity in the cat

The capacity of prostaglandins E1 (PGE1) and E2 (PGE2) to influence the lethal dose and lethal myocardial content of ouabain was studied in intact cats and cats whose spinal cords had been transected. The administration of PGE1 and PGE2 to intact cats was associated with an increase in lethal dose and ventricular content of ouabain. Spinal cord transection alone was also associated with an increase in lethal dose and ventricular content of ouabain. The administration of either PGE1 and PGE2 to animals whose spinal cords had been transected changed neither the lethal dose nor the lethal ventricular content of ouabain compared with cats whose spinal cords were transected but who received only ouabain. The present data suggest that PGE1 and PGE2 are effective agents for prophylaxis of ouabain-induced arrhythmias in the cat. The failure to observe an additional antiarrhythmic effect in animals whose spinal cords had been transected implies that the nervous system plays an important role in the antiarrhythmic action of the prostaglandins.