Experiments on isolated perfused rat heart showed that dalargin, an antagonist of μ- and δ-opioid receptors, favors a decrease in the parameters of contractility of intact myocardium, while not influencing the pumping function (systolic and diastolic contractility) of reperfused myocardium. At the same time, des-Tyr-dalargin (the non-opioid analog of dalargin) suppresses the contractility of both the intact heart and the isolated myocardium subjected to global ischemia and reperfusion. Both dalargin and des-Tyr-dalargin reduced the incidence of reperfusion-induced arrhythmia, but did not affect the coronary flow before ischemia and after restoration of the coronary flow. It is suggested that the effect of dalargin is related to activation of the cardiac δ-opioid receptors, while the inotropic action of des-Tyr-dalargin involves other receptor mechanisms.
|Number of pages||5|
|Journal||Eksperimental'naya i Klinicheskaya Farmakologiya|
|Publication status||Published - 2004|
ASJC Scopus subject areas
- Pharmacology, Toxicology and Pharmaceutics(all)