Electrically induced tachyarrhythmia and the effect of propranolol on the release of cyclic AMP and prostaglandin E by the canine left ventricle.
In anesthetized open-chest dogs, tachyarrhythmia (TA) was electrically induced by above-threshold stimuli via the right ventricle. During TA, a significant increase in the release of PGE and cAMP was observed in the canine coronary sinus blood (CSB). The efflux of cAMP corresponded with a concomitant increase in the left ventricular tissue level of this nucleotide. Pretreatment with propranolol (1.0 mg/kg i.v.) prevented the TA-induced changes in the level of PGE as well as cAMP in the CSB and in the tissue levels of cAMP. There was an increase in the activity of phosphorylase a in the myocardial tissue during TA which could be abolished by propranolol pretreatment. These results suggest possible interrelationships among catecholamines, cAMP, and PGE.
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002304:Cardiac Pacing, Artificial; D003326:Coronary Circulation / Q000187:drug effects; D000242:Cyclic AMP / Q000378:metabolism*; D015237:Dinoprost; D004285:Dogs; D006339:Heart Rate / Q000187:drug effects*; D006352:Heart Ventricles / Q000187:drug effects / Q000201:enzymology; D009206:Myocardium / Q000201:enzymology*; D010762:Phosphorylase a / Q000378:metabolism; D011433:Propranolol / Q000494:pharmacology*; D011458:Prostaglandins E / Q000378:metabolism*; D011460:Prostaglandins F / Q000378:metabolism; D011942:Receptors, Adrenergic, alpha / Q000187:drug effects
D011458:Prostaglandins E; D011460:Prostaglandins F; D011942:Receptors, Adrenergic, alpha; D011433:Propranolol; D015237:Dinoprost; D000242:Cyclic AMP; D010762:Phosphorylase a