Effects of the Neuropeptide Y (NPY)-Receptor Antagonist BIBP3226 on Vascular NPY-Receptors with Different Ligand Requirements

Neuropeptide Y (NPY), one of the most abundant peptides in rat and human brains, appears to act in the hypothalamus to stimulate feeding. It was first suggested that the NPY Y1 receptor (Y1R) was involved in feeding stimulated by NPY. More recently a novel NPY receptor subtype (Y5R) was identified in rat and human as the NPY feeding receptor subtype. There is, however, no absolute consensus since selective Y1R antagonists also antagonize NPY-induced hyperphagia. Nevertheless, new anti-obesity drugs may emerge from further pharmacological characterization of the NPY receptors and their antagonists. A large panel of Y1R and Y5R antagonists (such as CGP71683A, BIBO3304, BIBP3226, 1229U91, and SYNAPTIC and BANYU derivatives but also patentable in-house-synthesized compounds) have been evaluated through in vitro and in vivo tests in an attempt to establish a predictive relationship between the binding selectivity for human receptors, the potency in isolated organs assays, and the inhibitory effect on food intake in both normal and obese hyperphagic rodents. Although these results do not allow one to conclude on the implication of a single receptor subtype at the molecular level, this approach is crucial for the design of novel NPY receptor antagonists with potential use as anti-obesity drugs and for evaluation of their possible adverse peripheral side effects, such as hypotension.Key words: obesity, weight reduction, food intake, neuropeptide Y, rodents.

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Autoreceptor-induced inhibition of neuropeptide Y release from PC-12 cells is mediated by Y2 receptors

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1997.273.4.h1737 ◽

1997 ◽

Vol 273 (4) ◽

pp. H1737-H1744 ◽

Cited By ~ 12

Author(s):

Xiaoli Chen ◽

Debora A. Dimaggio ◽

Song Ping Han ◽

Thomas C. Westfall

Keyword(s):

Neuropeptide Y ◽

Peptide Yy ◽

Dependent Manner ◽

Inhibitory Effects ◽

Ideal Model ◽

Concentration Dependent Manner ◽

Pc 12 Cells ◽

Npy Receptor ◽

Neuropeptide Y Release ◽

Npy Receptors

Pheochromocytoma (PC)-12 cells express Y1, Y2, and Y3 neuropeptide Y (NPY) receptors when differentiated with nerve growth factor (NGF). The present work evaluated NGF-differentiated PC-12 cells as a model system to study modulation of NPY release by NPY autoreceptors. We demonstrated that both K+ and nicotine stimulated concomitant release of NPY and dopamine from differentiated PC-12 cells. We also showed in this study that NPY release from PC-12 cells was attenuated in a concentration-dependent manner by peptide YY (PYY)-(13—36), a selective agonist for the Y2 type of NPY receptors. This result demonstrated that NPY release could be modulated by NPY autoreceptors of the Y2 subtype. The inhibitory action of PYY-(13—36) may be mediated at least in part by inhibition of N-type Ca2+channels, because PYY-(13—36) could not produce further inhibitory effects in the presence of a maximum effective concentration of ω-conotoxin, an N-type Ca2+-channel blocker. The inhibition by PYY-(13—36) could be blocked by pretreatment of cells with pertussis toxin, suggesting that an inhibitory GTP-binding protein was involved. Furthermore, the function of NPY autoreceptors could be modulated by other receptors such as β-adrenergic and ATP receptors. The evoked release of NPY was also attenuated by ATP and adenosine, which have been shown to be colocalized and coreleased with NPY from sympathetic nerve terminals. These results suggest that PC-12 cells differentiated with NGF may be an ideal model to study regulatory mechanisms of NPY release and that autoreceptor-mediated regulation of NPY release appears to act through the Y2 subtype of the NPY receptor.

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Establishment of robust functional assays for the characterization of neuropeptide Y (NPY) receptors: identification of 3-(5-benzoyl-thiazol-2-ylamino)-benzonitrile as selective NPY type 5 receptor antagonist

Neuropharmacology ◽

10.1016/j.neuropharm.2005.01.020 ◽

2005 ◽

Vol 48 (7) ◽

pp. 1043-1055 ◽

Cited By ~ 13

Author(s):

Frank M. Dautzenberg ◽

Jacqueline Higelin ◽

Philippe Pflieger ◽

Werner Neidhart ◽

Wolfgang Guba

Keyword(s):

Neuropeptide Y ◽

Receptor Antagonist ◽

Functional Assays ◽

Npy Receptors

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Neuropeptide Y—Mediated Constriction and Dilation in Rat Middle Cerebral Arteries

Journal of Cerebral Blood Flow & Metabolism ◽

10.1097/00004647-200101000-00010 ◽

2001 ◽

Vol 21 (1) ◽

pp. 77-84 ◽

Cited By ~ 37

Author(s):

Junping You ◽

Lars Edvinsson ◽

Robert M. Bryan

Keyword(s):

Nitric Oxide ◽

Smooth Muscle ◽

Vascular Smooth Muscle ◽

Neuropeptide Y ◽

Cerebral Arteries ◽

Npy Receptor ◽

Middle Cerebral Arteries ◽

Oxide Synthase ◽

Npy Receptors ◽

Stimulation Of

Neuropeptide Y (NPY) is an important vasoconstrictor in the cerebral circulation. Its constrictor response is because of activation of NPY receptors on the vascular smooth muscle (VSM). Little is known regarding the effects of NPY on the endothelium. In the current study, the authors tested the hypothesis that NPY can either constrict or dilate rat middle cerebral arteries (MCAs). Constriction is elicited by stimulating receptors on the VSM; dilation is elicited by stimulating receptors on the endothelium. Middle cerebral arteries were isolated, cannulated with micropipettes, pressurized to 85 mm Hg, and luminally perfused. The extraluminal application of NPY (mixed agonist), [Leu31, Pro34]-NPY (Y1 agonist), or NPY-[13–36] (Y2 agonist) produced concentration-dependent constrictions. BIBP 3226 (Y1 selective antagonist) significantly attenuated the NPY-and [Leu31, Pro34]-NPY–induced constrictions. The luminal application of NPY, [Leu31, Pro34]-NPY, and NPY-[13–36] produced concentration-dependent dilations of MCAs. The maximum dilation produced by the NPY receptor agonists was approximately 40% of the dilation elicited by the luminal administration of 10−5 mol/L ATP. Dilations elicited by luminal NPY, [Leu31, Pro34]-NPY, or NPY-[13–36] were abolished by inhibition of nitric oxide synthase with 10−5 mol/L Nω-nitro-L-arginine methyl ester (L-NAME) or removal of the endothelium. Dilations produced by luminal NPY or luminal [Leu31, Pro34]-NPY were not affected by BIBP 3226. Stimulation of NPY receptors on vascular smooth muscle constricted MCAs. Stimulation of an NPY receptor other than the Y1 subtype on endothelium dilated the MCAs by releasing nitric oxide.

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Placental Neuropeptide Y (NPY) and NPY receptors expressions and serum NPY levels in preeclampsia

Experimental Biology and Medicine ◽

10.1177/1535370219831437 ◽

2019 ◽

Vol 244 (5) ◽

pp. 380-388 ◽

Cited By ~ 3

Author(s):

Roongrit Klinjampa ◽

Chantacha Sitticharoon ◽

Xaynaly Souvannavong-Vilivong ◽

Chanakarn Sripong ◽

Issarawan Keadkraichaiwat ◽

...

Keyword(s):

Neuropeptide Y ◽

Gestational Age ◽

Receptor Expression ◽

Clinical Parameters ◽

Expression Ratio ◽

Y1 Receptor ◽

Placental Angiogenesis ◽

Y2 Receptor ◽

Npy Receptor ◽

Npy Receptors

Neuropeptide Y (NPY) has been reported as a vasoconstrictive substance that might be associated with preeclampsia. NPY mediates different effects via its specific NPY receptors. NPY action via Y1 receptor (Y1R) and/or Y5 receptor (Y5R) induces vascular smooth muscle cells proliferation while it is implicated in angiogenesis via Y2 receptor (Y2R) and/or Y5R. The objectives of this study were to (1) compare placental NPY, Y1 receptor ( Y1R), Y2 receptor ( Y2R), and Y5 receptor ( Y5R) expressions between normal (NP) and preeclamptic (PE) pregnancies to determine whether gene expression of different NPY receptors are altered in the PE condition; (2) compare maternal serum NPY levels between NP and PE subjects; and (3) determine correlations between placental gene expressions as well as serum NPY levels with maternal and neonatal clinical parameters. There were 22 subjects each in the NP (gestational age 37–42 weeks) and PE (gestational age ≥34 weeks) groups. Clinical parameters and serum NPY levels were measured before delivery. NPY expression and serum NPY levels were comparable between NP and PE subjects. Y1R, Y2R, and Y5R expressions were significantly lower in PE than NP subjects. In all and NP subjects, placental Y2R showed the highest expression, tended to be higher than Y5R, and was significantly higher than Y1R. In PE subjects, placental Y2R was comparable to Y5R and both Y2R and Y5R were significantly higher than Y1R. The NPY receptor expression ratio between the PE/NP groups showed that it was lowest for Y2R (0.27) compared to Y1R (0.42) and Y5R (0.40) suggestive of decreased Y2R expression in PE subjects. In summary, a decrease in placental Y2R mRNA might be associated with abnormalities of placental angiogenesis which probably contributes to the pathophysiology of preeclampsia. The roles of NPY receptors mediating placental vascularization need to be further investigated. Impact statement Neuropeptide Y (NPY) has been reported as a vasoconstrictive substance which might be associated with preeclampsia. The novel findings of this study were that Y1R, Y2R, and Y5R expressions were significantly lower in the PE than the NP group. Moreover, the NPY receptor expression ratio between the PE/NP groups was lowest for Y2R (0.27) compared to Y1R (0.42) and Y5R (0.40) suggestive of a reduction of this receptor in the preeclampsia group. Our results suggested that decreased Y2R mRNA in the PE group might be associated with abnormalities of placental angiogenesis which probably contributes to the pathophysiology of preeclampsia.

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Orexigenic effect of the melanocortin MC4 receptor antagonist HS014 is inhibited only partially by neuropeptide Y Y1 receptor selective antagonists

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y99-124 ◽

2000 ◽

Vol 78 (2) ◽

pp. 143-149 ◽

Cited By ~ 10

Author(s):

Ants Kask ◽

Helgi B Schiöth ◽

Jaanus Harro ◽

Jarl ES Wikberg ◽

Lembit Rägo

Keyword(s):

Food Intake ◽

Neuropeptide Y ◽

Receptor Antagonist ◽

Male Rats ◽

Receptor Antagonists ◽

Y1 Receptor ◽

Npy Receptor ◽

Inhibit Food Intake ◽

In Vitro Data

Neuropeptide Y (NPY) and melanocortin (MC) peptides have opposite effects on food intake: NPY-like peptides and MC receptor antagonists stimulate feeding and increase body weight, whereas melanocortins and NPY antagonists inhibit food intake. In this study we tested whether the orexigenic effect of the selective MC4 receptor antagonist HS014 (1 nmol) could be inhibited by three different NPY antagonists, (R)-N2-(diphenylacetyl)-N-[(4-hydroxy-phenyl)methyl]- D-argininamide (BIBP3226), (R)-N-[[4-(aminocarbonylaminomethyl)-phenyl]methyl]-N2-(diphenylacetyl)-argininamide-trifluoroacetate (BIBO3304), and decapeptide [D-Tyr27,36D-Thr32]NPY27-36, after icv administration in freely feeding male rats. All three NPY receptor antagonists inhibited the orexigenic effects of HS014 partially and with markedly different potency. [D-Tyr27,36D-Thr32]NPY27-36 was active only in subconvulsive dose. The NPY Y1 selective antagonist BIBP3226 was more effective in inhibiting the effect of HS014 than BIBO3304 despite in vitro data indicating that BIBP3226 is about 10 times less potent than BIBO3304 at NPY Y1 receptor. An enantiomer of BIBO3304, BIBO3457, failed to inhibit HS014-induced feeding, indicating that the effects of BIBO3304 were stereoselective. These results suggest that stimulation of food intake caused by weakening of melanocortinergic tone at the MC4 receptor is partially but not exclusively related to NPY Y1 receptor activation.Key words: neuropeptide Y, NPY Y1 receptor antagonist, BIBO3304, BIBP3226, [D-Tyr27,36D-Thr32]NPY(27-36), 1229U91, food intake, MC4 receptor antagonist, HS014.

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Evidence That the Inhibition of Luteinizing Hormone Secretion Exerted by Central Administration of Neuropeptide Y (NPY) in the Rat Is Predominantly Mediated by the NPY-Y5 Receptor Subtype1

Endocrinology ◽

10.1210/endo.140.9.6985 ◽

1999 ◽

Vol 140 (9) ◽

pp. 4046-4055 ◽

Cited By ~ 51

Author(s):

Paula D. Raposinho ◽

Pierre Broqua ◽

Dominique D. Pierroz ◽

Amanda Hayward ◽

Yvan Dumont ◽

...

Keyword(s):

Food Intake ◽

Neuropeptide Y ◽

Receptor Antagonist ◽

Pancreatic Polypeptide ◽

Inhibitory Action ◽

Receptor Subtypes ◽

Y1 Receptor ◽

Npy Receptor ◽

Gonadotropic Axis ◽

Lh Secretion

Abstract A number of studies have indicated that neuropeptide Y (NPY) is a central regulator of the gonadotropic axis, and the Y1 receptor was initially suggested to be implicated. As at least five different NPY receptor subtypes have now been characterized, the aim of the present study was to reinvestigate the pharmacological profile of the receptor(s) mediating the inhibitory action of NPY on LH secretion by using a panel of NPY analogs with different selectivity toward the five NPY receptor subtypes. When given intracerebroventricularly (icv) to castrated rats, a bolus injection of native NPY (0.7–2.3 nmol) dose-dependently decreased plasma LH. Peptide YY (PYY; 2.3 nmol) was as potent as NPY, suggesting that the Y3 receptor is not implicated. Confirming previous data, the mixed Y1, Y4, and Y5 agonist[ Leu31,Pro34]NPY (0.7–2.3 nmol) inhibited LH release with potency and efficacy equal to those of NPY. Neither the selective Y2 agonist C2-NPY (2.3 nmol) nor the selective Y4 agonist rat pancreatic polypeptide affected plasma LH, excluding Y2 and Y4 subtypes for the action of NPY on LH secretion. The mixed Y4-Y5 agonist human pancreatic polypeptide (0.7–7 nmol) as well as the mixed Y2-Y5 agonist PYY3–36 (0.7–7 nmol) that displayed very low affinity for the Y1 receptor, thus practically representing selective Y5 agonists in this system, decreased plasma LH with potency and efficacy similar to those of NPY, indicating that the Y5 receptor is mainly involved in this inhibitory action of NPY on LH secretion.[ d-Trp32]NPY, a selective, but weak, Y5 agonist, also inhibited plasma LH at a dose of 7 nmol. Furthermore, the inhibitory action of NPY (0.7 nmol) on LH secretion could be fully prevented, in a dose-dependent manner (6–100 μg, icv), by a nonpeptidic Y5 receptor antagonist. This antagonist (60 μg, icv) also inhibited the stimulatory action of NPY (0.7 nmol) on food intake. The selectivity of PYY3–36, human PP,[ d-Trp32]NPY, and the Y5 antagonist for the Y5 receptor subtype was further confirmed by their ability to inhibit the specific[ 125I][Leu31,Pro34]PYY binding to rat brain membrane homogenates in the presence of the Y1 receptor antagonist BIBP3226, a binding assay system that was described as being highly specific for Y5-like receptors. With the exception of[ d-Trp32]NPY, all analogs able to inhibit LH secretion were also able to stimulate food intake. Taken together, these results indicate that the Y5 receptor is involved in the negative control by NPY of the gonadotropic axis.

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Y5 Receptors Mediate Neuropeptide Y Actions at Excitatory Synapses in Area CA3 of the Mouse Hippocampus

Journal of Neurophysiology ◽

10.1152/jn.00532.2001 ◽

2002 ◽

Vol 87 (1) ◽

pp. 558-566 ◽

Cited By ~ 41

Author(s):

Hui Guo ◽

Peter A. Castro ◽

Richard D. Palmiter ◽

Scott C. Baraban

Keyword(s):

Synaptic Transmission ◽

Neuropeptide Y ◽

Critical Role ◽

Hippocampal Slices ◽

Receptor Subtype ◽

Limbic Seizures ◽

Excitatory Transmission ◽

Npy Receptor ◽

Bath Application ◽

Peptide Agonist

Neuropeptide Y (NPY) is a potent modulator of excitatory synaptic transmission and limbic seizures. NPY is abundantly expressed in the dentate gyrus and is thought to modulate hippocampal excitability via activation of presynaptic Y2 receptors (Y2R). Here we demonstrate that NPY, and commonly used Y2R-preferring (NPY13–36) and Y5 receptor (Y5R)–preferring ([d-Trp32]NPY and hPP) peptide agonists, evoke similar levels of inhibition at excitatory CA3 synapses in hippocampal slices from wild-type control mice (WT). In contrast, NPYergic inhibition of excitatory CA3 synaptic transmission is absent in mice lacking the Y5R subtype (Y5R KO). In both analyses of evoked population spike activity and spontaneous excitatory postsynaptic synaptic currents (EPSCs), NPY agonists induced powerful inhibitory effects in all hippocampal slices from WT mice, whereas these peptides had no effect in slices from Y5R KO mice. In slices from WT mice, NPY (and NPY receptor–preferring agonists) reduced the frequency of spontaneous EPSCs but had no effect on sEPSC amplitude, rise time, or decay time. Furthermore, NPYergic modulation of spontaneous EPSCs in WT mice was mimicked by bath application of a novel Y5R-selective peptide agonist ([cpp]hPP) but not the selective Y2R agonist ([ahx5–24]NPY). In situ hybridization was used to confirm the presence of NPY, Y2, and Y5 mRNA in the hippocampus of WT mice and the absence of Y5R in knockout mice. These results suggest that the Y5 receptor subtype, previously believed to mediate food intake, plays a critical role in modulation of hippocampal excitatory transmission at the hilar-to-CA3 synapse in the mouse.

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