CHARACTERIZATION OF THE OPIOID RECEPTOR SUBTYPES MEDIATING THE NEGATIVE INOTROPIC EFFECTS OF DAMGO, DPDPE AND U-50,488H IN ISOLATED HUMAN RIGHT ATRIA STRIPS
F. Llobell et Ml. Laorden, CHARACTERIZATION OF THE OPIOID RECEPTOR SUBTYPES MEDIATING THE NEGATIVE INOTROPIC EFFECTS OF DAMGO, DPDPE AND U-50,488H IN ISOLATED HUMAN RIGHT ATRIA STRIPS, Neuropeptides, 29(2), 1995, pp. 115-119
The present investigation was aimed at elucidating if mu, delta- and k
appa-opioid receptors are involved in the effects of DAMGO (selective
mu-agonist), DPDPE (selective delta-agonist) and U-50,488H (selective
kappa-agonist) in isolated electrically driven human right atria strip
s. The negative inotropic effects induced by the opioid agonists used
in this study were not antagonized in presence of naloxone (preferenti
ally mu-antagonist), naltrindole (selective delta-antagonist) and nor-
binaltorphimine (selective kappa-antagonist). These data suggest that
the opioid receptors are not involved in the cardiac depressant effect
s induced by mu-, delta- and kappa-opioid agonists.