Characterization of specific δ-opioid binding sites in the distal small intestine of swine

Research output: Contribution to journalArticlepeer-review

1 Scopus citations


Delta-opioid receptors modulate neurogenic smooth muscle contractions and mucosal ion transport in the porcine distal small intestine. We compared specific δ-opioid binding sites in neuronal membranes isolated from the inner submucosal plexus and myenteric plexus of this gut region. In both preparations, the δ-opioid receptor antagonist naltrindole displaced [3H]diprenorphine from two binding sites. [3H]Naltrindole bound specifically to a single high-affinity site that was displaced by δ-opioid receptor ligands with the rank order of affinity: naltriben >7-benzylidenenaltrexone>deltorphin II>[D-Pen2, D-Pen 5] enkephalin. Relative decreases in δ-opioid receptor agonist affinity in the presence of Na+ and other ions differed in submucosal and myenteric membranes. The κ-opioid receptor antagonist norbinaltorphimine displaced [3H]naltrindole binding in myenteric membranes (Ki=7.2 nM). Delta-opioid receptors in submucosal and myenteric plexuses of porcine ileum appear to differ in some respects.

Original languageEnglish (US)
Pages (from-to)111-116
Number of pages6
JournalEuropean Journal of Pharmacology
Issue number1-3
StatePublished - Dec 15 2003

Bibliographical note

Funding Information:
This investigation was supported in part by National Institutes of Health grants R01 DA-10200 and T32 DA-07234.


  • Diprenorphine (Pig)
  • Enteric nervous system
  • Naltrindole
  • Opioid receptor


Dive into the research topics of 'Characterization of specific δ-opioid binding sites in the distal small intestine of swine'. Together they form a unique fingerprint.

Cite this