PYY inhibits CCK-stimulated pancreatic secretion through the area postrema in unanesthetized rats.
Peptide YY (PYY) inhibits CCK-8-secretin-stimulated pancreatic secretion in vivo. To investigate whether CCK-8-secretin-stimulated pancreatic secretion is mediated through a vago-vagal pathway and whether PYY inhibits this pathway through the area postrema (AP), chronic pancreatic, biliary, and duodenal catheters were implanted in AP-lesioned (APX) or sham-operated rats. The effects of APX on pancreatic secretion stimulated by bethanechol, pancreatic juice diversion (PJD), or CCK-8-secretin, were tested, with and without background PYY infusion, in unanesthetized rats. APX reduced basal pancreatic secretion by 15-20% (P < 0.01). APX had no effect on bethanechol-stimulated secretion and potentiated protein secretion stimulated by PJD (396 vs. 284%) and exogenous CCK-8-secretin. In sham-operated rats, background PYY potently inhibited CCK-8-secretin-stimulated pancreatic fluid (1.8 vs. 48.2%) and protein secretion (3.7 vs. 45.8%) but potentiated fluid (52.9 vs. 43.1%) and protein (132.9 vs. 68.9%) secretion in APX rats. Our findings demonstrate that PYY inhibits CCK-8-secretin-stimulated pancreatic secretion through an AP-dependent mechanism in sham-operated rats. The AP also contributes to basal pancreatic secretion.
Deng
X
X
Division of Gastroenterology, Hepatology and Nutrition, Department of Medicine, University of Pittsburgh, 3550 Terrace St., Pittsburgh, PA 15261, USA.
Guarita
D R
DR
Pedroso
M R
MR
Kreiss
C
C
Wood
P G
PG
Sved
A F
AF
Whitcomb
D C
DC
D000818:Animals; D001933:Brain Stem / Q000187:drug effects / Q000502:physiology* / Q000601:surgery; D008297:Male; D010179:Pancreas / Q000378:metabolism*; D019894:Peptide YY / Q000494:pharmacology / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D012633:Secretin / Q000494:pharmacology; D012844:Sincalide / Q000494:pharmacology*
D019894:Peptide YY; D012633:Secretin; D012844:Sincalide