The novel opioid antagonist [dially-Tyr1,(CH2)S-Phe4,Leu5]enkephalin (M154,129) was examined for its ability to block the antisecretory effects of [D-Ala2,D-Leu5]enkephalin (DADLE) in isolated mucosal segments of the guinea-pig ileum, actions mediated predominantly through the δ opiate receptor. DADLE reduced transepithelial potential difference and short-circuit current (ED50 18 nM); these effects were competitively antagonized by M154,129 with a Ke value of 746 nM. These results are consistent with others demonstrating that M154,129 is a relatively selective although not highly potent blocker of δ opiate receptors.
- δ Opiate receptor Intestinal electrolyte transport
ASJC Scopus subject areas