THE ACTION OF LOPERAMIDE IN INHIBITING PROSTAGLANDIN‐INDUCED INTESTINAL SECRETION IN THE RAT

• Published in: British journal of pharmacology 1981-11, Vol.74 (3), p.563-569
• Main Authors: HARDCASTLE, JACQUELINE, HARDCASTLE, P.T., READ, N.W., REDFERN, J.S.
• Format: Article
• Language: English
• Subjects: Animals; Chlorides - metabolism; Cyclic AMP - biosynthesis; In Vitro Techniques; Intestinal Mucosa - metabolism; Intestinal Mucosa - physiology; Loperamide - pharmacology; Male; Membrane Potentials - drug effects; Piperidines - pharmacology; Prostaglandin Antagonists; Rats; Sodium - metabolism
• ISSN: 0007-1188; 1476-5381
• DOI: 10.1111/j.1476-5381.1981.tb10465.x

1 The mechanisms by which loperamide inhibits the intestinal secretion induced by prostaglandin E2 were investigated in rat jejunum. 2 In vivo loperamide prevented prostaglandin‐induced fluid secretion but did not reduce the associated rise in the transintestinal potential difference. 3 In intestinal sheets the electrical response to prostaglandin E2 was enhanced in the presence of loperamide. 4 The ionic basis of these changes was determined by measuring Na+ and Cl− fluxes across intestinal sheets. Loperamide did not reduce the prostaglandin‐induced increase in net Cl− secretion, although it prevented the inhibition of mucosal‐to‐serosal Na+ movement. 5 Loperamide does not alter cyclic adenosine 3′,5′‐monophosphate (cyclic AMP) levels by a direct action at the enterocyte, since in isolated enterocytes neither basal nor prostaglandin‐stimulated cyclic AMP levels were affected by the drug.