Inhibition of PGE1 induced intestinal secretion by the synthetic enkephalin analogue FK 33-824.
1. The effects of the enkephalin analogue, FK 33-824 were compared with those of morphine and naloxone on the prostaglandin E1-induced increase in intestinal fluid volume and unanaesthetized and pithed rats. 2. FK 33-824 inhibits the prostaglandin E1-induced increase in intestinal fluid volume both in unanaesthetized and pithed rats. 3. Naloxone abolished the inhibitory effect of FK 33-824 in both experimental models. 4. It can be concluded from the experiments in pithed rats that the inhibitory effect of FK 33-824, like that of morphine, on prostaglandin E1-induced secretion is caused by a peripheral action. 5. It is assumed that endogenous enkephalins protect against prostaglandin-mediated loss of fluid into the gut lumen. This protective effect can be mimicked by an enkephalin analogue and blocked by naloxone.
D000818:Animals; D004723:Endorphins / Q000494:pharmacology*; D004745:Enkephalins / Q000494:pharmacology*; D005260:Female; D006207:Half-Life; D007413:Intestinal Mucosa / Q000378:metabolism; D007422:Intestines / Q000187:drug effects*; D009020:Morphine / Q000494:pharmacology; D009270:Naloxone / Q000494:pharmacology; D011458:Prostaglandins E / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D051381:Rats
D004723:Endorphins; D004745:Enkephalins; D011458:Prostaglandins E; D009270:Naloxone; D009020:Morphine