Antisecretory mechanisms of peptide YY in rat distal colon.
Peptide YY (PYY) is a potent regulator of intestinal secretion. These studies investigated the role of Y1 and Y2 receptor subtypes in mediating the antisecretory effects of PYY on mucosa-submucosa preparations of rat distal colon. Addition of vasoactive intestinal peptide (VIP) to these tissues resulted in a 140 +/- 18% increase in basal short-circuit current (Isc) and the induction of Cl- secretion. VIP-stimulated increases in Isc were abolished by the addition of each of PYY, (Pro34)-PYY, a Y1 receptor-selective agonist, and PYY-(3-36), an endogenous Y2 receptor-selective ligand. However, when tissue neural transmission was blocked with tetrodotoxin, neither PYY nor its receptor subtype-selective analogs were able to inhibit VIP-stimulated increases in Isc. These results suggest that in the rat distal colon, the antisecretory actions of PYY are mediated through a combination of Y1 and Y2 receptor subtypes or through a novel receptor subtype that is unable to discriminate between (Pro34)-PYY and PYY-(3-36).
Whang
E E
EE
Department of Surgery, UCLA School of Medicine, USA.
Hines
O J
OJ
Reeve
J R
JR
Grandt
D
D
Moser
J A
JA
Bilchik
A J
AJ
Zinner
M J
MJ
McFadden
D W
DW
Ashley
S W
SW
D000818:Animals; D003106:Colon / Q000294:innervation / Q000378:metabolism*; D005768:Gastrointestinal Hormones / Q000494:pharmacology / Q000502:physiology*; D017136:Ion Transport; D008297:Male; D010446:Peptide Fragments; D019894:Peptide YY; D010455:Peptides / Q000494:pharmacology / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D011964:Receptors, Gastrointestinal Hormone / Q000819:agonists / Q000145:classification / Q000502:physiology*; D014660:Vasoactive Intestinal Peptide / Q000494:pharmacology
D005768:Gastrointestinal Hormones; D010446:Peptide Fragments; D010455:Peptides; D011964:Receptors, Gastrointestinal Hormone; C082172:peptide YY receptor; C091928:peptide YY, Pro(34)-; D019894:Peptide YY; C061785:peptide YY (3-36); D014660:Vasoactive Intestinal Peptide