| Title | Peripheral peptide YY inhibits propulsive colonic motor function through Y2 receptor in conscious mice. | | Author(s) | Wang L, Gourcerol G, Yuan PQ, Wu SV, Million M, Larauche M, Taché Y | | Institution | 1UCLA. | | Source | Am J Physiol Gastrointest Liver Physiol 2009 Nov 5. | | Abstract | Peptide YY (PYY) antisecretory effect on intestinal epithelia is well established while less is known about its actions to influence colonic motility in conscious animals. We characterized changes in basal and stimulated colonic motor function induced by PYY-related peptides in conscious mice. PYY(3-36), PYY and neuropeptipde Y (NPY) (8 nmol/kg) injected intraperitoneally (ip) inhibited fecal pellet output (FPO)/h during novel environment stress by 90%, 63% and 57% respectively while the Y(1) preferring agonists, [Pro(34)]PYY and [Leu(31),Pro(34)]NPY had no effect. Corticotrophin-releasing factor 2 receptor antagonist did not alter PYY(3-36) inhibitory action. PYY and PYY(3-36) significantly reduced restraint-stimulated defecation, and PYY(3-36) inhibited high amplitude distal colonic contractions as recorded in restrained conscious mice for 1 h recorded by intraluminal pressure using a microtransducer. PYY suppression of 5-hydroxytryptophan (5-HTP, ip)-induced FPO and diarrhea was blocked by Y(2) antagonist, BIIE0246, injected ip and mimicked by PYY(3-36) but not [Leu(31), Pro(34)]NPY. PYY(3-36) also inhibited bethanechol-stimulated FPO and diarrhea. PYY(3-36) inhibited basal FPO during nocturnal feeding period and light phase in fasted/refed mice for 2-3 h while the reduction of food intake lasted only for 1 h. PYY(3-36) delayed gastric emptying after fasting-refeeding by 48% and distal colonic transit time by 104% while [Leu(31),Pro(34)]NPY had no effect. In the proximal and distal colon, higher Y(2) mRNA expression was detected in the mucosa than muscle layers and Y(2) immunoreactivity was located in nerve terminals around myenteric neurons. These data established that PYY/PYY(3-36) potently inhibits basal and stress/5-HT/cholinergic stimulated propulsive colonic motor function in conscious mice likely via Y(2) receptors. | | Language | ENG | | Pub Type(s) | JOURNAL ARTICLE
| | PubMed ID | 19892938 |
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