Effects of Met-enkephalin and naloxone on gastric emptying and secretion in rhesus monkeys.
Recent studies have demonstrated the presence of enkephalins in gastric neurons and endocrine cells; however, their role in the regulation of gastric function is unknown. The effect of Met-enkephalin (MET), the stable analogue of Met-enkephalin [D-Ala2]Met-enkephalinamide (DMET), and the opiate receptor antagonist naloxone were studied in five chair-adapted rhesus monkeys. A dye-dilution technique was used to determine simultaneously fractional emptying rate, hydrogen, sodium, potassium, and chloride ion output, and fluid output. Both MET and DMET significantly inhibited fractional emptying rate and H+ secretion following an 80-ml water meal. Only MET, however, significantly altered fluid and sodium ion output. Naloxone had no effect on gastric function following the water meal.
D000818:Animals; D004305:Dose-Response Relationship, Drug; D004743:Enkephalin, Leucine / Q000031:analogs & derivatives / Q000494:pharmacology; D016308:Enkephalin, Leucine-2-Alanine / Q000031:analogs & derivatives*; D004744:Enkephalin, Methionine / Q000494:pharmacology*; D005746:Gastric Emptying / Q000187:drug effects*; D005750:Gastric Juice / Q000187:drug effects / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D008253:Macaca mulatta; D008297:Male; D009270:Naloxone / Q000494:pharmacology*
D009270:Naloxone; D004744:Enkephalin, Methionine; D004743:Enkephalin, Leucine; D016308:Enkephalin, Leucine-2-Alanine; C030279:enkephalinamide-Leu, Ala(2)-