PYY-preferring receptor in the dorsal vagal complex and its involvement in PYY stimulation of gastric acid secretion in rats.
1. Microinjection of peptide YY (PYY, 7-46 pmol) into the dorsal vagal complex (DVC) stimulated gastric acid secretion in urethane-anaesthetized rats. Using a variety of neuropeptide Y (NPY) and PYY derivatives, we characterized the pharmacological profile of the receptor mediating the acid secretory response to PYY. 2. [Pro34]rat(r)/porcine(p)PYY and [Pro34]human(h)PYY (23-117 pmol), microinjected unilaterally into the DVC resulted in a similar maximal increase in net acid secretion reaching 68+/-11 and 89+/-31 micromol 90 min(-1) respectively. 3. Rat/hNPY and pNPY (47 pmol) microinjected into the DVC induced a similar net gastric acid secretion (27+/-8 and 23+/-8 micromol 90 min(-1) respectively) and a higher dose (116 pmol) tended to reduce the response. 4. Pancreatic polypeptide (PP, 4-46 pmol), [Leu31,Pro34]r/hNPY (47 and 117 pmol) and the Y2 selective agonists, hPYY3-36, pNPY5-36 and PNPY13-36 (25-168 pmol) microinjected into the DVC failed to influence basal gastric acid secretion. 5. The rank order of potency of PYY > or = [Pro34]r/pPYY = [Pro34]hPYY> r/hNPY = pNPY to stimulate gastric acid secretion upon injection into the DVC and the ineffectiveness of PP, [Leu31,Pro34]NPY and C-terminal NPY/PYY fragments suggest that a PYY-preferring receptor subtype may be involved in mediating the stimulating effect.
Yang
H
H
CURE: Digestive Diseases Research Center, West Los Angeles Veterans Affairs Medical Center, UCLA, CA 90073, USA.
Li
W P
WP
Reeve
J R
JR
Rivier
J
J
Taché
Y
Y
D000818:Animals; D005744:Gastric Acid / Q000378:metabolism*; D005753:Gastric Mucosa / Q000378:metabolism; D006801:Humans; D008297:Male; D008845:Microinjections; D019894:Peptide YY / Q000494:pharmacology*; D010455:Peptides / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D011964:Receptors, Gastrointestinal Hormone / Q000378:metabolism*; D013268:Stimulation, Chemical; D013552:Swine; D014630:Vagus Nerve / Q000378:metabolism*
D010455:Peptides; D011964:Receptors, Gastrointestinal Hormone; C082172:peptide YY receptor; D019894:Peptide YY