Affinage

GALR1

Galanin receptor type 1 · UniProt P47211

Length
349 aa
Mass
39.0 kDa
Annotated
2026-04-28
71 papers in source corpus 25 papers cited in narrative 25 extracted findings

Mechanistic narrative

Synthesis pass · prose summary of the discoveries below

GALR1 is a Gi/o-coupled galanin receptor that functions as an inhibitory modulator of neuronal excitability, nociception, seizure susceptibility, and affective behavior. Upon galanin binding to a hydrophobic pocket involving His264, Phe282, Glu271, Phe115, and Phe186, GALR1 inhibits adenylyl cyclase, activates MAPK via Gβγ subunits, opens inwardly rectifying K⁺ channels, and inhibits N- and P/Q-type voltage-dependent calcium channels, followed by rapid clathrin-dependent receptor internalization (PMID:9578554, PMID:9370372, PMID:9649336, PMID:18602374, PMID:12915763). GALR1 knockout mice exhibit spontaneous seizures and enhanced hippocampal injury in status epilepticus models, establishing GALR1 as the primary mediator of galanin's anticonvulsant and neuroprotective actions, and high-dose spinal galanin antinociception also operates through GALR1 (PMID:12487125, PMID:15350653, PMID:11481429). GALR1 forms heteroreceptor complexes with GalR2 and with 5-HT1A/GPR39 that alter ligand selectivity and downstream signaling, and its transcription is repressed by the E-box-binding factor Scratch2 and positively regulated by cAMP/CREB-dependent mechanisms (PMID:25152404, PMID:26365466, PMID:34108238, PMID:15934937).

Mechanistic history

Synthesis pass · year-by-year structured walk · 13 steps
  1. 1995 High

    Cloning of rat GALR1 established it as a high-affinity galanin receptor coupled to pertussis-toxin-sensitive Gi protein that inhibits cAMP, resolving the molecular identity of the first galanin receptor subtype.

    Evidence cDNA cloning, radioligand binding in COS1 cells, cAMP assay with pertussis toxin in CHO cells

    PMID:8750821

    Open questions at the time
    • Downstream effectors beyond cAMP not yet characterized
    • In vivo relevance not tested
    • Receptor subtype selectivity unknown
  2. 1997 High

    Site-directed mutagenesis and genomic characterization defined the ligand-binding pocket architecture of GALR1, identifying His264, Phe282, Glu271, and Phe115 as key determinants of galanin recognition and revealing a unique three-exon gene structure.

    Evidence Site-directed mutagenesis with radioligand binding and adenylyl cyclase assays; genomic cloning of mouse GalR1

    PMID:9271210 PMID:9370372

    Open questions at the time
    • No crystal or cryo-EM structure available
    • Contributions of extracellular loop residues not yet mapped
  3. 1998 High

    Characterization of GALR1 signaling revealed that it activates MAPK through Gβγ subunits (not PKC), displays two-affinity-state binding, and undergoes rapid agonist-induced internalization, establishing the full proximal signaling and trafficking repertoire.

    Evidence CHO and HEK293E cell transfection with βARKct blockade, MAPK assay, fluorescein-galanin internalization by flow cytometry, receptor alkylation studies

    PMID:9578554 PMID:9649336 PMID:9808667

    Open questions at the time
    • Internalization machinery (arrestin involvement) not identified
    • Recycling versus degradation fate unknown
  4. 2001 High

    Selective agonist pharmacology in vivo demonstrated that spinal antinociception at high galanin doses is specifically mediated by GALR1, separating it from GalR2-mediated pronociceptive effects and establishing GALR1 as a therapeutic target for neuropathic pain.

    Evidence Intrathecal GalR1/2 agonist AR-M961 vs GalR2-selective AR-M1896 in rat Bennett neuropathic pain model with allodynia testing

    PMID:11481429

    Open questions at the time
    • Spinal circuit identity of GalR1-expressing neurons unknown
    • Whether GALR1 is sufficient or only necessary for antiallodynia not resolved
  5. 2002 High

    GALR1 knockout mice showed spontaneous seizures and reduced IGF-I, proving GALR1 is required for galanin's anticonvulsant function and contributes to neuroendocrine homeostasis — the first genetic loss-of-function evidence for a galanin receptor in vivo.

    Evidence Insertional gene knockout, seizure monitoring, IGF-I radioimmunoassay; further refined by Phe186 mutagenesis of the binding pocket

    PMID:11983932 PMID:12487125

    Open questions at the time
    • Seizure mechanism (circuit vs molecular) not dissected
    • Compensatory changes in GalR2/R3 not assessed
  6. 2003 High

    Electrophysiology in brain slices revealed that GALR1 mediates postsynaptic inhibition by activating inwardly rectifying K⁺ channels in arcuate nucleus neurons, defining the ionic mechanism underlying GALR1's inhibitory actions on neuronal excitability.

    Evidence Sharp microelectrode recordings in brain slices with galantide antagonism, TTX, and post-hoc in situ hybridization for GalR1 mRNA

    PMID:12915763

    Open questions at the time
    • Specific GIRK channel subunit identity not determined
    • Whether this mechanism generalizes to all GALR1-expressing neurons unknown
  7. 2004 High

    Model-specific analysis in GALR1 knockouts demonstrated that GALR1's neuroprotective role extends to hippocampal cell survival during status epilepticus (pilocarpine and perforant path models) but not kainic acid seizures, revealing stimulus-dependent engagement of the receptor.

    Evidence GalR1 knockout mice in three SE models, FluoroJade B and TUNEL staining, BrdU neurogenesis labeling

    PMID:15350653

    Open questions at the time
    • Why kainic acid seizures bypass GALR1 is unexplained
    • Downstream neuroprotective effectors not identified at this stage
  8. 2005 Medium

    GALR1 expression itself is regulated by cAMP/CREB signaling — a feedback loop whereby Gi-mediated cAMP suppression by galanin normally restrains GALR1 levels, while loss of galanin tone increases CREB phosphorylation and upregulates GALR1.

    Evidence Western blot and mRNA quantification in Cath.a cells and galanin knockout mice with cAMP manipulation and CREB phosphorylation analysis

    PMID:15934937

    Open questions at the time
    • Whether CREB directly binds the GALR1 promoter not shown
    • Feedback dynamics under physiological conditions not measured
  9. 2007 High

    GALR1 was shown to inhibit N- and P/Q-type calcium channels via Gαi-βγ subunits and to act purely postsynaptically in spinal cord, further distinguishing its effector repertoire from GalR2's presynaptic actions.

    Evidence Patch-clamp in NTS neurons with selective agonist M617, Gαi antibody dialysis; whole-cell recordings in spinal substantia gelatinosa slices with receptor-selective agonists

    PMID:17910903 PMID:18602374

    Open questions at the time
    • Calcium channel subunit specificity (α1 subunit identity) not determined
    • Mechanism of voltage-dependent relief not fully resolved
  10. 2014 Medium

    Discovery that GALR1 forms heteroreceptor complexes with GalR2 (shifting galanin fragment selectivity and Gi vs Gq coupling bias) and promotes chemoresistance in colorectal cancer by suppressing caspase-8/FLIPL-dependent apoptosis expanded GALR1's roles beyond classical neuromodulation.

    Evidence PLA and BRET2 for heteromer detection with CRE/NFAT reporters; RNAi screening in CRC cells with caspase-8 and FLIPL Western blots

    PMID:22859720 PMID:25152404

    Open questions at the time
    • GalR1-GalR2 heteromer existence in native neurons not confirmed
    • FLIPL regulation mechanism (transcriptional vs post-translational) not resolved
    • Cancer relevance based on cell lines only
  11. 2017 Medium

    GALR1 was identified as the specific receptor subtype mediating galanin's neuroprotection against ischemic injury, acting through inhibition of caspase-8 and caspase-12 (but not caspase-9), potentially via cPKCγ signaling.

    Evidence MCAO/reperfusion model, OGD in primary neurons, lentiviral GalR1 knockdown, cPKCγ knockout neurons, caspase activity assays

    PMID:28203483

    Open questions at the time
    • cPKCγ link is correlative, not yet confirmed by rescue experiments
    • Whether caspase-8 inhibition in ischemia and cancer share the same mechanism unknown
  12. 2018 Medium

    Region-specific GALR1 knockdown in prefrontal cortex alleviated depression-like behavior and restored CREB-BDNF-5-HT signaling, directly linking cortical GALR1 activity to suppression of monoaminergic and neurotrophic pathways relevant to mood.

    Evidence siRNA knockdown of GALR1 in rat PFC, behavioral tests, Western blot, HPLC for 5-HT

    PMID:30487761

    Open questions at the time
    • Cell-type specificity of PFC GALR1 effects not determined
    • Whether CREB-BDNF suppression is direct or secondary to cAMP inhibition unclear
  13. 2021 Medium

    Identification of Scratch2 as a transcriptional repressor of GALR1 via an E-box element in the promoter provided the first defined transcription factor regulating GALR1 expression and linked this regulation to stress-induced depression-like behavior.

    Evidence Promoter reporter assays, Scratch2 knockdown in rat ventral PAG, RNAscope in situ hybridization, behavioral testing

    PMID:34108238

    Open questions at the time
    • Direct Scratch2 binding to GALR1 promoter not shown by ChIP
    • Whether Scratch2 regulation is brain-region specific not addressed

Open questions

Synthesis pass · forward-looking unresolved questions
  • Key unresolved questions include the structural basis of GALR1 activation (no experimental structure), the identity of arrestin/scaffolding proteins mediating internalization, whether GalR1-GalR2 and GalR1-5HT1A heteromers exist in native brain tissue, and the cell-type-specific circuit mechanisms by which GALR1 controls seizure threshold and affective behavior.
  • No experimental 3D structure of GALR1
  • Heteromer formation unconfirmed in vivo
  • Circuit-level mechanism of anticonvulsant action not resolved

Mechanism profile

Synthesis pass · controlled-vocabulary classification · explore literature graph →
Molecular activity
GO:0060089 molecular transducer activity 6 GO:0098772 molecular function regulator activity 3
Localization
GO:0005886 plasma membrane 3 GO:0005768 endosome 1
Pathway
R-HSA-162582 Signal Transduction 8 R-HSA-112316 Neuronal System 5 R-HSA-5357801 Programmed Cell Death 2
Partners
GALGALR2GPR39HTR1A
Complex memberships
GalR1-5-HT1A-GPR39 heterocomplexGalR1-GalR2 heteromer

Evidence

Reading pass · 25 per-paper findings extracted from the source corpus
Year Finding Method Journal Conf PMIDs
1998 GalR1 couples to Gi protein to inhibit adenylyl cyclase (cAMP production), and activates MAPK through a Gi-betagamma signaling pathway (sensitive to beta-ARKct inhibition but not PKC inhibition), while failing to couple to Gs or Gq/G11. CHO cell transfection, cAMP assay, pertussis toxin treatment, beta-ARKct expression, PKC inhibitor treatment, MAPK assay Biochemistry High 9578554
1995 Rat GALR1 is a G protein-coupled receptor that binds galanin with high affinity and inhibits basal and forskolin-stimulated cAMP formation via a pertussis toxin-sensitive G protein in CHO cells. cDNA cloning, radioligand binding in COS1 cells, cAMP assay with pertussis toxin in CHO cells Brain research. Molecular brain research High 8750821
1997 Site-directed mutagenesis of GalR1 identified His264 and Phe282 as directly involved in galanin binding (mutation reduces binding 20-fold but retains partial cAMP signaling), Glu271 interacts with the N-terminus of galanin, and Phe115 in TM III is structurally important for the ligand binding pocket. Site-directed mutagenesis, radioligand binding, adenylyl cyclase inhibition assay European journal of biochemistry High 9370372
1998 The N-terminal portion of galanin binds to a hydrophobic pocket within GalR1, and ligand binding is followed by rapid GalR1-mediated internalization of the agonist-receptor complex via an energy-requiring endocytic process (t1/2 ~10 min, ~78% internalization, blocked by sucrose). Fluorescein-galanin (F-Gal) probe, fluorescence quenching by KI, flow cytometry in transfected CHO cells, temperature and sucrose inhibition controls Biochemistry High 9649336
2002 Molecular modelling and mutagenesis of hGALR1 identified Phe186 in the second extracellular loop as making hydrophobic contact with galanin (Ala7/Leu11); Glu271 interacts with the N-terminus of galanin; Phe115 is structurally important to the binding pocket; and Phe282 interacts with Trp2 of galanin via an aromatic-aromatic interaction. Molecular modelling based on frog rhodopsin alpha-carbon maps, site-directed mutagenesis, radioligand binding with subtype-selective ligands Protein engineering High 11983932
1998 Human GALR1 expressed in HEK293E cells shows two affinity states (picomolar and nanomolar), inhibits forskolin-stimulated cAMP, and stimulates GTPgammaS binding; chimeric galanin peptides including M40 act as full agonists at GALR1 in vitro despite antagonist effects in vivo. Stable episomal expression in HEK293E cells, saturation binding isotherms, SPA assay, cAMP inhibition assay, GTPgammaS binding, receptor inactivation by partial alkylation The Journal of pharmacology and experimental therapeutics High 9808667
2008 GalR1 activation by the selective agonist M617 inhibits N- and P/Q-type voltage-dependent calcium channels via Galphai-protein betagamma subunits in rat nucleus tractus solitarius neurons. Patch-clamp whole-cell recording, selective GalR1 agonist M617, depolarizing prepulse protocol, intracellular dialysis of Galphai antibody, M35 antagonist Brain research High 18602374
2003 GalR1 mediates direct postsynaptic inhibitory actions of galanin on arcuate nucleus neurons by activating an inwardly-rectifying K+ conductance (reversal potential ~-94 mV), confirmed by co-expression of Gal-R1 mRNA in responsive neurons and blockade by galantide. Sharp microelectrode current-clamp recordings in brain slices, biocytin filling, in situ hybridization for Gal-R1 mRNA, TTX treatment, galantide antagonism Neuroendocrinology High 12915763
2007 GalR1 activation in substantia gelatinosa neurons activates an inwardly-rectifying conductance and has little effect on presynaptic spontaneous EPSCs, while GalR2 activation decreases membrane excitability and acts presynaptically to reduce EPSC frequency; consistent with GalR1 coupling to Gi/o. Whole-cell patch-clamp recording in rat spinal cord slices, selective GalR1 agonist cocktail (AR-M961 + M871), selective GalR2 agonist AR-M1896 Pain High 17910903
2014 GalR1 and its ligand galanin promote chemoresistance in colorectal cancer; silencing GalR1 induces caspase-8-dependent apoptosis by downregulating the caspase-8 inhibitor FLIPL. RNAi functional screening, siRNA knockdown, apoptosis assays, Western blot for caspase-8 and FLIPL Clinical cancer research Medium 22859720
2005 GalR1 protein levels in the locus coeruleus are regulated by cAMP-dependent mechanisms: GalR1 (but not GalR2 or GalR3) is upregulated in LC-like Cath.a cells by cAMP elevation and is increased in galanin knockout mice where loss of galanin-maintained cAMP tone leads to increased CREB phosphorylation and elevated GalR1 expression. Western blot, mRNA quantification in cell lines and knockout mice, cAMP manipulation, CREB phosphorylation analysis Journal of neurochemistry Medium 15934937
2002 GALR1 knockout mice exhibit spontaneous tonic-clonic seizures and reduced circulating IGF-I levels, demonstrating that GALR1 is required for galanin's anti-seizure activity and for neuroendocrine regulation. Insertional gene knockout, seizure monitoring, IGF-I radioimmunoassay Brain research. Molecular brain research High 12487125
2004 GalR1 mediates galanin's protection from seizures and hippocampal injury in Li-pilocarpine and perforant path stimulation models of status epilepticus but not in kainic acid-induced seizures, as shown by more severe seizures and greater CA1 and hilar cell injury in GalR1 knockout mice. GalR1 knockout mice, Li-pilocarpine, electrical PPS, and kainic acid SE models, FluoroJade B, TUNEL staining, BrdU neurogenesis labeling Neuroscience High 15350653
2001 Low-dose galanin-induced spinal pronociception is mediated by GalR2 receptors, while high-dose galanin antiallodynic effects in neuropathic pain are mediated by GalR1 receptors, established by comparing equimolar doses of the GalR2-selective agonist AR-M1896 and the GalR1/2 agonist AR-M961 in rat spinal cord. Intrathecal infusion/injection, selective GalR2 agonist AR-M1896, GalR1/2 agonist AR-M961, Bennett neuropathic pain model, von Frey and cold allodynia testing Proceedings of the National Academy of Sciences of the United States of America High 11481429
2003 Spinal antinociception by intrathecal galanin is mediated by GalR1 receptors, and galanin synergizes with morphine and the NMDA antagonist AP-5 at the spinal level, as shown by isobolographic analysis. Intrathecal injection, formalin test with automated flinch detection, isobolographic analysis, comparison of GalR1/2 agonist vs GalR2-selective agonist potencies The Journal of pharmacology and experimental therapeutics Medium 14610237
2014 GalR1 and GalR2 form heteroreceptor complexes (GalR1-GalR2 heteromers) in HEK293T cells, demonstrated by proximity ligation assay and BRET2; within the complex, the GalR1 protomer has increased affinity for galanin(1-15) vs galanin(1-29), preferentially inhibiting CREB via Gi, while GalR2 mediates Gq/11-dependent NFAT signaling. Proximity ligation assay, BRET2, CRE luciferase reporter assay, NFAT reporter assay, selective antagonists (M35, M871) Biochemical and biophysical research communications Medium 25152404
2015 GalR1 forms heteroreceptor complexes with 5-HT1A and GPR39, demonstrated by FRET and co-immunopurification; the GalR1-5-HT1A-GPR39 heterocomplex shows different signaling compared to individual homo/monomeric receptors, and this complex formation is modulated by zinc. FRET, co-immunopurification, functional signaling assays, zinc treatment Biochimica et biophysica acta Medium 26365466
2017 GalR1 mediates galanin's neuroprotection against ischemic injury by inhibiting caspase-8 and caspase-12-initiated apoptosis (but not caspase-9), potentially via cPKCgamma signaling; GalR2/3 agonist did not replicate the effect and lentiviral GalR1 knockdown abolished galanin-induced neuroprotection. MCAO/reperfusion mouse model, OGD in primary neurons, lentiviral RNAi knockdown of GalR1, GalR2/3 agonist AR-M1896, caspase activity assays, cPKCgamma knockout neurons Aging and disease Medium 28203483
2021 The transcription factor Scratch2 binds to an E-box element in the GalR1 promoter region (-250 to -220) to repress GalR1 gene expression; decreased Scratch2 in the ventral PAG of chronically stressed rats leads to elevated GalR1 expression and depression-like behavior. Promoter reporter assays, Scratch2 binding to E-box (in vitro molecular biology), Scratch2 knockdown in rat vPAG, behavioral testing, RNAscope in situ hybridization Proceedings of the National Academy of Sciences of the United States of America Medium 34108238
1997 GALR1 mRNA is co-expressed in extrahypothalamic vasopressin/galanin neurons (~95% co-expression) but is absent from cholinergic neurons in the medial septum/diagonal band, suggesting galanin modulates basal forebrain cholinergic activity indirectly rather than via direct GalR1 action on cholinergic neurons. Double in situ hybridization histochemistry with GALR1 and choline acetyltransferase or vasopressin/galanin riboprobes Brain research. Molecular brain research Medium 9450684
1997 Mouse GalR1 coding sequence is uniquely divided into three exons: exon 1 encodes N-terminal region through TM5, exon 2 encodes the third intracellular loop, and exon 3 encodes TM6 through the C-terminus; the receptor functionally inhibits cAMP when expressed from cDNA. Genomic cloning, cDNA cloning, functional cAMP assay in transfected cells FEBS letters Medium 9271210
2005 Under standard autoradiographic binding conditions, [125I]-galanin binding in mouse brain is exclusively attributable to GalR1 (not GalR2 or GalR3), as no specific binding was detected in any brain region of GalR1 knockout mice. Autoradiographic radioligand binding in GalR1 knockout vs wild-type and galanin knockout mouse brain sections Neuroscience High 15708483
2018 GALR1 knockdown in the prefrontal cortex of postpartum depression model rats alleviates depressive-like behavior and reverses downregulation of CREB-BDNF signaling and 5-HT levels, implicating GalR1 in PFC in suppressing CREB/BDNF/5-HT pathways. siRNA knockdown of GALR1 in rat PFC, behavioral tests, Western blot for CREB-BDNF signaling, HPLC for 5-HT measurement Frontiers in psychiatry Medium 30487761
2007 GAL-R1 and GAL-R2 (but not GAL-R3) are expressed in rat adrenocortical cells and mediate galanin-stimulated corticosterone secretion via the adenylate cyclase/PKA-dependent signaling pathway (not phospholipase C/PKC), as shown by immunoblockade of receptors and pharmacological inhibitors. RT-PCR, [3H]galanin binding with receptor immunoblockade, cAMP and inositol triphosphate assays, adenylate cyclase and PKA inhibitors, corticosterone RIA International journal of molecular medicine Medium 17143559
2024 GalR1 is predominantly expressed in glutamatergic neurons in both the ventral PFC and ventral hippocampus; optogenetic excitation of GalR1-expressing neurons in the vPFC (but not vHC) disrupts visuospatial attention; vPFC GalR1 neurons increase activity during correct attentive actions while vHC GalR1 neurons increase activity during impulsive errors. Multiplex fluorescent in situ hybridization, novel viral approach for GalR1-expressing neuron targeting, optogenetics, fiber photometry, 5-choice serial reaction time task bioRxivpreprint Medium bio_10.1101_2024.07.29.605653

Source papers

Stage 0 corpus · 71 papers · ranked by NIH iCite citations
Year Title Journal Citations PMID
1999 Expression of the novel galanin receptor subtype GALR2 in the adult rat CNS: distinct distribution from GALR1. The Journal of comparative neurology 282 10379831
1998 Differential intracellular signaling of the GalR1 and GalR2 galanin receptor subtypes. Biochemistry 212 9578554
1995 Cloning and characterization of the rat GALR1 galanin receptor from Rin14B insulinoma cells. Brain research. Molecular brain research 196 8750821
2001 Receptor subtype-specific pronociceptive and analgesic actions of galanin in the spinal cord: selective actions via GalR1 and GalR2 receptors. Proceedings of the National Academy of Sciences of the United States of America 181 11481429
2003 Galanin GAL-R1 receptor null mutant mice display increased anxiety-like behavior specific to the elevated plus-maze. Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology 161 12700679
2004 Patterns of seizures, hippocampal injury and neurogenesis in three models of status epilepticus in galanin receptor type 1 (GalR1) knockout mice. Neuroscience 79 15350653
2002 Critical role for GALR1 galanin receptor in galanin regulation of neuroendocrine function and seizure activity. Brain research. Molecular brain research 77 12487125
2004 Learning and memory performance in mice lacking the GAL-R1 subtype of galanin receptor. The European journal of neuroscience 66 15016096
1997 Semiquantitative distribution of galanin-receptor (GAL-R1) mRNA-containing cells in the male rat hypothalamus. Neuroendocrinology 65 9380273
1997 Genomic organization and functional characterization of the mouse GalR1 galanin receptor. FEBS letters 64 9271210
2004 Characterization of GalR1, GalR2, and GalR3 immunoreactivity in catecholaminergic nuclei of the mouse brain. The Journal of comparative neurology 60 15514977
2003 Galanin acts at GalR1 receptors in spinal antinociception: synergy with morphine and AP-5. The Journal of pharmacology and experimental therapeutics 58 14610237
2009 Analyzing the validity of GalR1 and GalR2 antibodies using knockout mice. Naunyn-Schmiedeberg's archives of pharmacology 57 19159918
2012 Identification of galanin and its receptor GalR1 as novel determinants of resistance to chemotherapy and potential biomarkers in colorectal cancer. Clinical cancer research : an official journal of the American Association for Cancer Research 51 22859720
1999 Evidence for expression of galanin receptor Gal-R1 mRNA in certain gonadotropin releasing hormone neurones of the rostral preoptic area. Journal of neuroendocrinology 49 10520130
2003 Altered hippocampal expression of neuropeptides in seizure-prone GALR1 knockout mice. Epilepsia 47 12887433
2005 Galanin impairs performance on learning and memory tasks: findings from galanin transgenic and GAL-R1 knockout mice. Neuropeptides 37 15944016
1997 Pharmacological characterization and tissue distribution of the human and rat GALR1 receptors. Biochemical and biophysical research communications 37 9168941
2014 Preferential activation by galanin 1-15 fragment of the GalR1 protomer of a GalR1-GalR2 heteroreceptor complex. Biochemical and biophysical research communications 36 25152404
2000 Expression of GalR1 and GalR2 galanin receptor messenger ribonucleic acid in proopiomelanocortin neurons of the rat arcuate nucleus: effect of testosterone. Endocrinology 36 10803589
2010 Engineering galanin analogues that discriminate between GalR1 and GalR2 receptor subtypes and exhibit anticonvulsant activity following systemic delivery. Journal of medicinal chemistry 35 20121116
2015 The zinc binding receptor GPR39 interacts with 5-HT1A and GalR1 to form dynamic heteroreceptor complexes with signaling diversity. Biochimica et biophysica acta 33 26365466
2000 Upregulation of galanin binding sites and GalR1 mRNA levels in the mouse locus coeruleus following chronic morphine treatments and precipitated morphine withdrawal. Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology 33 10882839
1998 Evidence for hydrophobic interaction between galanin and the GalR1 galanin receptor and GalR1-mediated ligand internalization: fluorescent probing with a fluorescein-galanin. Biochemistry 33 9649336
1998 Effects of estrous cyclicity on the expression of the galanin receptor Gal-R1 in the rat preoptic area: a comparison with the male. Endocrinology 31 9751492
1997 Structural organization of the mouse and human GALR1 galanin receptor genes (Galnr and GALNR) and chromosomal localization of the mouse gene. Genomics 30 9367674
2005 GalR1, but not GalR2 or GalR3, levels are regulated by galanin signaling in the locus coeruleus through a cyclic AMP-dependent mechanism. Journal of neurochemistry 29 15934937
2007 Selective stimulation of GalR1 and GalR2 in rat substantia gelatinosa reveals a cellular basis for the anti- and pro-nociceptive actions of galanin. Pain 28 17910903
2002 Molecular modelling and site-directed mutagenesis of human GALR1 galanin receptor defines determinants of receptor subtype specificity. Protein engineering 28 11983932
1997 Mutagenesis and ligand modification studies on galanin binding to its GTP-binding-protein-coupled receptor GalR1. European journal of biochemistry 27 9370372
2011 The neuropeptide galanin and variants in the GalR1 gene are associated with nicotine dependence. Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology 26 21796100
2005 [125I]-Galanin binding in brain of wildtype, and galanin- and GalR1-knockout mice: strain and species differences in GalR1 density and distribution. Neuroscience 26 15708483
1997 GALR1 galanin receptor mRNA is co-expressed by galanin neurons but not cholinergic neurons in the rat basal forebrain. Brain research. Molecular brain research 25 9450684
2012 Pharmacogenetic association of the galanin receptor (GALR1) SNP rs2717162 with smoking cessation. Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology 24 22373943
2013 GALR1 methylation in vaginal swabs is highly accurate in identifying women with endometrial cancer. International journal of gynecological cancer : official journal of the International Gynecological Cancer Society 23 23727823
2015 Epigenetic inactivation of galanin and GALR1/2 is associated with early recurrence in head and neck cancer. Clinical & experimental metastasis 22 26572146
2005 Human galanin (GAL) and galanin 1 receptor (GALR1) variations are not involved in fat intake and early onset obesity. The Journal of nutrition 22 15930442
2018 Inhibition of GALR1 in PFC Alleviates Depressive-Like Behaviors in Postpartum Depression Rat Model by Upregulating CREB-BNDF and 5-HT Levels. Frontiers in psychiatry 20 30487761
2005 Increased hyperalgesia after tissue injury and faster recovery of allodynia after nerve injury in the GalR1 knockout mice. Neuropeptides 20 15944015
2023 Alleviation of Limosilactobacillus reuteri in polycystic ovary syndrome protects against circadian dysrhythmia-induced dyslipidemia via capric acid and GALR1 signaling. NPJ biofilms and microbiomes 19 37422471
1998 Pharmacological and biochemical characterization of a recombinant human galanin GALR1 receptor: agonist character of chimeric galanin peptides. The Journal of pharmacology and experimental therapeutics 19 9808667
2017 Galanin Protects from Caspase-8/12-initiated Neuronal Apoptosis in the Ischemic Mouse Brain via GalR1. Aging and disease 18 28203483
2003 Direct inhibitory action of galanin on hypothalamic arcuate nucleus neurones expressing galanin receptor Gal-r1 mRNA. Neuroendocrinology 17 12915763
2018 Galanin/GalR1-3 system: A promising therapeutic target for myocardial ischemia/reperfusion injury. Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie 16 30551408
1998 Molecular identification and coexpression of galanin and GalR-1 galanin receptor in the human ocular ciliary epithelium: differential modulation of their expression by the activation of alpha2- and beta2-adrenergic receptors in cultured ciliary epithelial cells. Journal of neurochemistry 16 9832123
2014 Central injection of GalR1 agonist M617 facilitates GLUT4 expression in cardiac muscle of type 2 diabetic rats. Experimental gerontology 14 25449850
2007 Galanin enhances corticosterone secretion from dispersed rat adrenocortical cells through the activation of GAL-R1 and GAL-R2 receptors coupled to the adenylate cyclase-dependent signaling cascade. International journal of molecular medicine 14 17143559
2008 Variation in Galr1 expression determines susceptibility to exocitotoxin-induced cell death in mice. Genes, brain, and behavior 13 18363852
2008 Immunohistochemical localization of galanin receptors (GAL-R1, GAL-R2, and GAL-R3) on myenteric neurons from the sheep and dog stomach. Annals of anatomy = Anatomischer Anzeiger : official organ of the Anatomische Gesellschaft 13 18595677
2004 Regulation of galanin receptor GalR1 mRNA expression by ovarian steroids in oestrogen receptor alpha-immunoreactive neurones: identification of distinct populations of neurones in the preoptic area. Journal of neuroendocrinology 13 14764000
2022 Galanin Receptors (GALR1, GALR2, and GALR3) Immunoexpression in Enteric Plexuses of Colorectal Cancer Patients: Correlation with the Clinico-Pathological Parameters. Biomolecules 12 36551197
2008 Galanin inhibits calcium channels via Galpha(i)-protein mediated by GalR1 in rat nucleus tractus solitarius. Brain research 12 18602374
1998 Mutagenesis study on human galanin receptor GalR1 reveals domains involved in ligand binding. Annals of the New York Academy of Sciences 11 9928161
2021 Cell-type specific expression and behavioral impact of galanin and GalR1 in the locus coeruleus during opioid withdrawal. Addiction biology 10 33768673
2021 Regulatory Influence of Galanin and GALR1/GALR2 Receptors on Inflamed Uterus Contractility in Pigs. International journal of molecular sciences 10 34203944
2016 Central injection of GALR1 agonist M617 attenuates diabetic rat skeletal muscle insulin resistance through the Akt/AS160/GLUT4 pathway. Mechanisms of ageing and development 10 27041232
2016 The Influence of Gastric Antral Ulcerations on the Expression of Galanin and GalR1, GalR2, GalR3 Receptors in the Pylorus with Regard to Gastric Intrinsic Innervation of the Pyloric Sphincter. PloS one 10 27175780
2005 Induction of galanin receptor-1 (GalR1) expression in external granule cell layer of post-natal mouse cerebellum. Journal of neurochemistry 10 15748163
2002 Expression of galanin receptor-1 (GALR1) in the rat trigeminal ganglia and molar teeth. Neuroscience research 10 11900829
2010 Characterization of the chicken galanin type I receptor (GalR1) and a novel GalR1-like receptor (GalR1-L). General and comparative endocrinology 8 20977910
2021 Involvement of Scratch2 in GalR1-mediated depression-like behaviors in the rat ventral periaqueductal gray. Proceedings of the National Academy of Sciences of the United States of America 6 34108238
2012 Galanin, through GalR1 but not GalR2 receptors, decreases motivation at times of high appetitive behavior. Behavioural brain research 6 23142608
2015 A Pyrosequencing Assay for the Quantitative Methylation Analysis of GALR1 in Endometrial Samples: Preliminary Results. BioMed research international 5 26504828
1998 Retrovirus-mediated expression of the GalR1 galanin receptor: implication for efficient stable expression of functional G protein-coupled receptors. Journal of receptor and signal transduction research 4 9879063
2024 Glyphosate-induced changes in the expression of galanin and GALR1, GALR2 and GALR3 receptors in the porcine small intestine wall. Scientific reports 3 38632282
2022 Promoter hypermethylation of GALR1 acts as an early epigenetic susceptibility event in colorectal carcinogenesis. Journal of human genetics 3 35606503
2020 Association Between Polymorphisms in the 5' Region of the GALR1 Gene and Schizophrenia in the Northern Chinese Han Population: A Case-Control Study. Neuropsychiatric disease and treatment 3 32606704
2025 GALR1 and PENK serve as potential biomarkers in invasive non-functional pituitary neuroendocrine tumours. Gene 2 40024300
2021 Time-restricted feeding prevents metabolic diseases through the regulation of galanin/GALR1 expression in the hypothalamus of mice. Eating and weight disorders : EWD 1 34370270
2026 Intravenous galanin (1-16) and a GalR1 agonist attenuate allodynia in rats with spared nerve injury. Pain reports 0 41822106
2025 The potential neuro-oncology link of GALR1 protein molecular mechanism in breast cancer: Expression in BT549 and MDA-MB-231 cells and its role in proliferation and migration. International journal of biological macromolecules 0 40032112