title: Naloxone-insensitive modulation of gastric acid output by [D-Met2,Pro5]enkephalinamide in rats.
abstract: Studies from our laboratory have previously shown that two opioid agonists (morphine and [D-Met2,Pro5]enkephalinamide) aggravate, whereas naloxone inhibits cold-restraint stress-induced ulceration in rats. In the present study the effects of these substances were examined using the Shay-model. Contrary to expectations, both naloxone and the opioid agonists decreased gastric acid output. Naloxone in combination with either opioid agonist failed to reverse their inhibitory action. Thus the secretory activity of the stomach may be modulated by opioids in both naloxone-reversible and irreversible ways.
authors.affiliation: Department of Pathophysiology, Semmelweis University Medical School, Budapest, Hungary.
authors.forename: M
authors.initials: M
authors.lastname: Till
authors.forename: D
authors.initials: D
authors.lastname: Szombath
authors.forename: T
authors.initials: T
authors.lastname: Gáti
authors.forename: J I
authors.initials: JI
authors.lastname: Székely
mesh_terms: D000818:Animals; D004744:Enkephalin, Methionine / Q000031:analogs & derivatives* / Q000494:pharmacology; D005744:Gastric Acid / Q000378:metabolism*; D008297:Male; D009020:Morphine / Q000494:pharmacology; D009270:Naloxone / Q000494:pharmacology*; D011708:Pylorus / Q000502:physiology; D051381:Rats; D011919:Rats, Inbred Strains; D013276:Stomach Ulcer / Q000503:physiopathology
chemical_list: D009270:Naloxone; D004744:Enkephalin, Methionine; C021717:enkephalin, Met(2)-ProNH2(5)-; D009020:Morphine