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Updated: Aug 18, 2026

Tracking Drug-induced Changes in Receptor Post-internalization Trafficking by Colocalizational Analysis
Published on: July 3, 2015
Opiate binding sites in mucosa of pig small intestine
F L Quito1, V S Seybold, D R Brown
1Department of Veterinary PathoBiology (Pharmacology Section), University of Minnesota, College of Veterinary Medicine, St. Paul 55108.
Abstract:
Opiates such as morphine have profound antidiarrheal and constipating actions due in part to their ability to modify intestinal ion transport. This study was undertaken to examine the presence of opiate binding sites in the porcine distal jejunum, a gut segment analogous to the human ileum. Specific binding sites for the tritiated, mu-selective opioid agonist [D-Ala2, N-Me-Phe4, Gly5-ol]enkephalin (DAMGO) were localized to the basal portion of villous and crypt cells of the intestinal epithelium by receptor autoradiography. These binding sites may represent enkephalin receptors capable of modulating active electrolyte transport.
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