The effect of D-Ala-2-Me-Phe-4-Met-(0)-Ol enkephalin on blood pressure, heart rate and digoxin-induced arrhythmias in the guinea pig.
The cardiovascular effects of D-Ala-2-Me-Phe-4-Met-(0)-Ol enkephalin were investigated after its administration into the fourth cerebroventricle of the guinea pig. This enkephalin is a synthetic Met-enkephalin analog that is more resistant to degradation and has a high affinity for opioid receptors. It produced a significant increase in blood pressure and decline in heart rate. At high concentrations, 100 micrograms/kg plus 100 micrograms/kg/hr in the fourth ventricle, it produced bradyarrhythmias that were sometimes fatal. At doses that did not alter survival or produce arrhythmia, namely 30 micrograms/kg plus 25 micrograms/kg/hr in the fourth ventricle, the response to digitalis was assessed. Significant leftward shifts in the relationships between digoxin and arrhythmia occurrence and development of fatal arrhythmias were observed. Thus, D-Ala-2-Me-Phe-4-Met-(0)-Ol enkephalin has definite cardiovascular effects that include potentiation of digoxin arrhythmias.
D000818:Animals; D001145:Arrhythmias, Cardiac / Q000139:chemically induced*; D001794:Blood Pressure / Q000187:drug effects*; D005405:D-Ala(2),MePhe(4),Met(0)-ol-enkephalin / Q000494:pharmacology*; D004077:Digoxin / Q000037:antagonists & inhibitors; D006168:Guinea Pigs; D006339:Heart Rate / Q000187:drug effects*; D007276:Injections, Intraventricular; D008297:Male
D005405:D-Ala(2),MePhe(4),Met(0)-ol-enkephalin; D004077:Digoxin