RESUMEN
The effect of Arginine Vasopressin [AVP] on coronary flow was studied in the isolated heart of adult male rabbits. Five doses of the hormone [10-25-50-100-500 pg/ml] were used to study their effects on the coronary flow. One group of experiments [n = 5] were administrated a constant infusion of AVP in a dose of 100 pg/ml for 5 minutes, after which Creatin-Phospho-kinase enzyme [CPK] release from the cardiac muscle was estimated. The results showed that there is a significant reduction in coronary flow with the use of the large two doses [100 and 500 pg/ml]. A significant dose-dependent depression of coronary flow was also observed [r = + 0.92]. Moreover, the results showed a significant increase [+ 80.29%] in the CPK release-from the hearts infused with AVP continuously for five minutes. The data obtained medicate that AVP is a potent coronary constrictor in high doses only and produces myocardial damage. It was also found that the cyclooxygenase inhibitor [Ketoprofen] in the dose used [20 ug/ml] did not alter the direct AVP coronary constrictor response