RT Journal Article SR Electronic T1 A Typical Y1 Receptor Regulates Feeding Behaviors: Effects of a Potent and Selective Y1 Antagonist, J-115814 JF Molecular Pharmacology JO Mol Pharmacol FD American Society for Pharmacology and Experimental Therapeutics SP 501 OP 505 DO 10.1124/mol.59.3.501 VO 59 IS 3 A1 Akio Kanatani A1 Mikiko Hata A1 Satoshi Mashiko A1 Akane Ishihara A1 Osamu Okamoto A1 Yuji Haga A1 Tomoyuki Ohe A1 Tetsuya Kanno A1 Naomi Murai A1 Yasuyuki Ishii A1 Takahiro Fukuroda A1 Takehiro Fukami A1 Masaki Ihara YR 2001 UL http://molpharm.aspetjournals.org/content/59/3/501.abstract AB Neuropeptide Y (NPY) is a potent feeding stimulant. The orexigenic effect of NPY might be caused in part by the action of Y1 receptors. However, the existence of multiple NPY receptors including a possible novel feeding receptor has made it difficult to determine the relative importance of the Y1 receptor in feeding regulation. Herein we certified that the Y1 receptor is a major feeding receptor of NPY by using the potent and selective Y1 antagonist (−)-2-[1-(3-chloro-5-isopropyloxycarbonylaminophenyl)ethylamino]-6-[2-(5-ethyl-4-methyl-1,3-thiazol-2-yl)ethyl]-4-morpholinopyridine (J-115814) and Y1 receptor-deficient (Y1−/−) mice. J-115814 displaced125I-peptide YY binding to cell membranes expressing cloned human, rat, and murine Y1 receptors withK i values of 1.4, 1.8, and 1.9 nM, respectively, and inhibited NPY (10 nM)-induced increases in intracellular calcium levels via human Y1 receptors (IC50 = 6.8 nM). In contrast, J-115814 showed low affinities for human Y2 (K i > 10 μM), Y4 (K i = 640 nM) and Y5 receptors (K i = 6000 nM). Intracerebroventricular (ICV) (10–100 μg) and intravenous (IV) (0.3–30 mg/kg) administration of J-115814 significantly and dose-dependently suppressed feeding induced by ICV NPY (5 μg) in satiated Sprague-Dawley rats. Intraperitoneal (IP) administration of J-115814 (3–30 mg/kg) significantly attenuated spontaneous feeding in db/db and C57BL6 mice. Feeding induced by ICV NPY (5 μg) was unaffected by IP-injected J-115814 (30 mg/kg) in Y1−/− mice and was suppressed in wild-type and Y5−/− mice. These findings clearly suggest that J-115814 inhibits feeding behaviors through the inhibition of the typical Y1 receptor. We conclude that the Y1 receptor plays a key role in regulating food intake.