title: Role of Y(2) receptors in the regulation of gastric tone in rats.
abstract: We set out to determine the effect of peptide YY(3-36) (PYY(3-36)) on the gastric muscle tone in conscious rats by measuring intragastric pressure (IGP) during intragastric nutrient drink infusion. After an overnight fast, a chronically implanted gastric fistula was connected to a custom-made nutrient drink infusion system and a catheter to measure IGP. IGP was measured before and during the infusion of a nutrient drink (Nutridrink; 0.5 ml/min) until 10 ml was infused. Rats were treated with PYY(3-36) (0, 33, and 100 pmol·kg(-1)·min(-1)) in combination with a subcutaneous injection of the Y(2) receptor antagonists JNJ31020028 (10 mg/kg) or BIIE0246 (2 mg/kg). Experiments were also performed after subdiaphragmatic vagotomy and after pretreatment with 3 ml of nutrient drink (to mimic a fed state). IGP was compared as the average IGP during nutrient infusion, represented as means ± SE and compared using ANOVA. PYY(3-36) dose dependently increased the IGP during nutrient infusion (4.7 ± 0.3, 5.7 ± 0.5 and 7.3 ± 0.7 mmHg; P < 0.01) while JNJ31020028 and BIIE0246 could block this increase [4.4 ± 0.5 (P < 0.001) and 4.8 ± 0.4 (P < 0.05) mmHg, respectively]. Also in vagotomized rats, PYY(3-36) was able to significantly increase the IGP during, an effect attenuated by JNJ31020028. BIIE0246 and JNJ31020028 were not able to decrease the IGP when no PYY(3-36) was administered. PYY(3-36) increased gastric tone through an Y(2) receptor-mediated mechanism that does not involve the vagus nerve. Y(2) receptor antagonists were not able to decrease gastric tone without exogenous administration of PYY(3-36), indicating that Y(2) receptors do not play a crucial role in the determination of gastric tone in physiological conditions.
authors.affiliation: Translational Research Center for Gastrointestinal Disorders, University of Leuven, Leuven, Belgium.
authors.forename: P
authors.initials: P
authors.lastname: Janssen
authors.forename: S
authors.initials: S
authors.lastname: Verschueren
authors.forename: A
authors.initials: A
authors.lastname: Rotondo
authors.forename: J
authors.initials: J
authors.lastname: Tack
mesh_terms: D000818:Animals; D001120:Arginine / Q000008:administration & dosage / Q000031:analogs & derivatives / Q000494:pharmacology; D001549:Benzamides / Q000494:pharmacology; D001552:Benzazepines / Q000008:administration & dosage / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D005786:Gene Expression Regulation / Q000502:physiology; D008297:Male; D009129:Muscle Tonus / Q000502:physiology*; D010446:Peptide Fragments; D019894:Peptide YY / Q000008:administration & dosage / Q000494:pharmacology; D010879:Piperazines / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D011964:Receptors, Gastrointestinal Hormone / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D013270:Stomach / Q000502:physiology*
chemical_list: D001549:Benzamides; D001552:Benzazepines; C547250:JNJ-31020028; D010446:Peptide Fragments; D010879:Piperazines; D011964:Receptors, Gastrointestinal Hormone; C082172:peptide YY receptor; D019894:Peptide YY; C061785:peptide YY (3-36); D001120:Arginine; C403256:BIIE 0246