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Record Information
Version3.6
Creation Date2012-09-06 15:00:23 UTC
Update Date2016-02-11 01:27:39 UTC
HMDB IDHMDB13897
Secondary Accession NumbersNone
Metabolite Identification
Common Name4-ene-Valproic acid
Description4-ene-Valproic acid is only found in individuals that have used or taken Valproic Acid. 4-ene-Valproic acid is a metabolite of Valproic Acid. 4-ene-valproic acid belongs to the family of Branched Fatty Acids. These are fatty acids containing a branched chain.
Structure
Thumb
Synonyms
ValueSource
4-En-valproic acidKegg
4-Ene-vpaKegg
4-En-valproateGenerator
2-N-Propyl-4-pentenoateGenerator
Chemical FormulaC8H14O2
Average Molecular Weight142.1956
Monoisotopic Molecular Weight142.099379692
IUPAC Name2-propylpent-4-enoic acid
Traditional Name4-Ene-VPA
CAS Registry NumberNot Available
SMILES
CCCC(CC=C)C(O)=O
InChI Identifier
InChI=1S/C8H14O2/c1-3-5-7(6-4-2)8(9)10/h3,7H,1,4-6H2,2H3,(H,9,10)
InChI KeyInChIKey=UMYDNZXEHYSVFY-UHFFFAOYSA-N
Chemical Taxonomy
ClassificationNot classified
Ontology
StatusExpected but not Quantified
Origin
  • Drug metabolite
  • Endogenous
  • Food
Biofunction
  • Cell signaling
  • Fuel and energy storage
  • Fuel or energy source
  • Membrane integrity/stability
  • Waste products
Application
  • Nutrients
  • Pharmaceutical, waste
  • Stabilizers
  • Surfactants and Emulsifiers
Cellular locations
  • Cytoplasm
  • Extracellular
  • Membrane
Physical Properties
StateSolid
Experimental Properties
PropertyValueReference
Melting PointNot AvailableNot Available
Boiling PointNot AvailableNot Available
Water SolubilityNot AvailableNot Available
LogPNot AvailableNot Available
Predicted Properties
PropertyValueSource
Water Solubility4.11 mg/mLALOGPS
logP2.21ALOGPS
logP2.49ChemAxon
logS-1.5ALOGPS
pKa (Strongest Acidic)5.06ChemAxon
Physiological Charge-1ChemAxon
Hydrogen Acceptor Count2ChemAxon
Hydrogen Donor Count1ChemAxon
Polar Surface Area37.3 Å2ChemAxon
Rotatable Bond Count5ChemAxon
Refractivity40.29 m3·mol-1ChemAxon
Polarizability16.07 Å3ChemAxon
Number of Rings0ChemAxon
Bioavailability1ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
Spectra
Spectra
Spectrum TypeDescriptionSplash Key
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, PositiveNot Available
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, PositiveNot Available
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, PositiveNot Available
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, NegativeNot Available
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, NegativeNot Available
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, NegativeNot Available
Biological Properties
Cellular Locations
  • Cytoplasm
  • Extracellular
  • Membrane
Biofluid Locations
  • Blood
  • Urine
Tissue Location
  • Kidney
  • Liver
Pathways
NameSMPDB LinkKEGG Link
Valproic Acid Metabolism PathwaySMP00635Not Available
Normal Concentrations
BiofluidStatusValueAgeSexConditionReferenceDetails
BloodExpected but not QuantifiedNot ApplicableNot AvailableNot AvailableTaking drug identified by DrugBank entry
  • Not Applicable
details
UrineExpected but not QuantifiedNot ApplicableNot AvailableNot AvailableTaking drug identified by DrugBank entry
  • Not Applicable
details
Abnormal Concentrations
Not Available
Associated Disorders and Diseases
Disease ReferencesNone
Associated OMIM IDsNone
DrugBank IDNot Available
DrugBank Metabolite IDDBMET00060
Phenol Explorer Compound IDNot Available
Phenol Explorer Metabolite IDNot Available
FoodDB IDNot Available
KNApSAcK IDNot Available
Chemspider ID94669
KEGG Compound IDC16648
BioCyc IDNot Available
BiGG IDNot Available
Wikipedia LinkNot Available
NuGOwiki LinkHMDB13897
Metagene LinkHMDB13897
METLIN IDNot Available
PubChem Compound104896
PDB IDNot Available
ChEBI ID410867
References
Synthesis ReferenceNot Available
Material Safety Data Sheet (MSDS)Not Available
General ReferencesNot Available

Enzymes

General function:
Involved in 4-aminobutyrate transaminase activity
Specific function:
Catalyzes the conversion of gamma-aminobutyrate and L-beta-aminoisobutyrate to succinate semialdehyde and methylmalonate semialdehyde, respectively. Can also convert delta-aminovalerate and beta-alanine.
Gene Name:
ABAT
Uniprot ID:
P80404
Molecular weight:
56438.405
References
  1. Overington JP, Al-Lazikani B, Hopkins AL: How many drug targets are there? Nat Rev Drug Discov. 2006 Dec;5(12):993-6. [17139284 ]
  2. Imming P, Sinning C, Meyer A: Drugs, their targets and the nature and number of drug targets. Nat Rev Drug Discov. 2006 Oct;5(10):821-34. [17016423 ]
  3. Loscher W: Anticonvulsant and biochemical effects of inhibitors of GABA aminotransferase and valproic acid during subchronic treatment in mice. Biochem Pharmacol. 1982 Mar 1;31(5):837-42. [6805473 ]
  4. Ha JH, Lee DU, Lee JT, Kim JS, Yong CS, Kim JA, Ha JS, Huh K: 4-Hydroxybenzaldehyde from Gastrodia elata B1. is active in the antioxidation and GABAergic neuromodulation of the rat brain. J Ethnopharmacol. 2000 Nov;73(1-2):329-33. [11025174 ]
  5. Semba J, Kuroda Y, Takahashi R: Potential antidepressant properties of subchronic GABA transaminase inhibitors in the forced swimming test in mice. Neuropsychobiology. 1989;21(3):152-6. [2559361 ]
  6. Rosenberg G: The mechanisms of action of valproate in neuropsychiatric disorders: can we see the forest for the trees? Cell Mol Life Sci. 2007 Aug;64(16):2090-103. [17514356 ]
General function:
Involved in transferase activity, transferring hexosyl groups
Specific function:
UDPGT is of major importance in the conjugation and subsequent elimination of potentially toxic xenobiotics and endogenous compounds. This isoform has specificity for phenols.
Gene Name:
UGT1A9
Uniprot ID:
O60656
Molecular weight:
59940.495
References
  1. Zhou SF, Zhou ZW, Yang LP, Cai JP: Substrates, inducers, inhibitors and structure-activity relationships of human Cytochrome P450 2C9 and implications in drug development. Curr Med Chem. 2009;16(27):3480-675. Epub 2009 Sep 1. [19515014 ]
General function:
Involved in peroxidase activity
Specific function:
May play an important role in regulating or promoting cell proliferation in some normal and neoplastically transformed cells.
Gene Name:
PTGS1
Uniprot ID:
P23219
Molecular weight:
68685.82
References
  1. Zhou SF, Zhou ZW, Yang LP, Cai JP: Substrates, inducers, inhibitors and structure-activity relationships of human Cytochrome P450 2C9 and implications in drug development. Curr Med Chem. 2009;16(27):3480-675. Epub 2009 Sep 1. [19515014 ]
General function:
Involved in monooxygenase activity
Specific function:
Cytochromes P450 are a group of heme-thiolate monooxygenases. In liver microsomes, this enzyme is involved in an NADPH-dependent electron transport pathway. It performs a variety of oxidation reactions (e.g. caffeine 8-oxidation, omeprazole sulphoxidation, midazolam 1'-hydroxylation and midazolam 4-hydroxylation) of structurally unrelated compounds, including steroids, fatty acids, and xenobiotics. Acts as a 1,8-cineole 2-exo-monooxygenase. The enzyme also hydroxylates etoposide.
Gene Name:
CYP3A4
Uniprot ID:
P08684
Molecular weight:
57255.585
References
  1. Preissner S, Kroll K, Dunkel M, Senger C, Goldsobel G, Kuzman D, Guenther S, Winnenburg R, Schroeder M, Preissner R: SuperCYP: a comprehensive database on Cytochrome P450 enzymes including a tool for analysis of CYP-drug interactions. Nucleic Acids Res. 2010 Jan;38(Database issue):D237-43. Epub 2009 Nov 24. [19934256 ]
General function:
Involved in monooxygenase activity
Specific function:
Cytochromes P450 are a group of heme-thiolate monooxygenases. In liver microsomes, this enzyme is involved in an NADPH-dependent electron transport pathway. It oxidizes a variety of structurally unrelated compounds, including steroids, fatty acids, and xenobiotics. This enzyme contributes to the wide pharmacokinetics variability of the metabolism of drugs such as S-warfarin, diclofenac, phenytoin, tolbutamide and losartan.
Gene Name:
CYP2C9
Uniprot ID:
P11712
Molecular weight:
55627.365
References
  1. Zhou SF, Zhou ZW, Yang LP, Cai JP: Substrates, inducers, inhibitors and structure-activity relationships of human Cytochrome P450 2C9 and implications in drug development. Curr Med Chem. 2009;16(27):3480-675. Epub 2009 Sep 1. [19515014 ]
  2. Preissner S, Kroll K, Dunkel M, Senger C, Goldsobel G, Kuzman D, Guenther S, Winnenburg R, Schroeder M, Preissner R: SuperCYP: a comprehensive database on Cytochrome P450 enzymes including a tool for analysis of CYP-drug interactions. Nucleic Acids Res. 2010 Jan;38(Database issue):D237-43. Epub 2009 Nov 24. [19934256 ]
General function:
Involved in monooxygenase activity
Specific function:
Responsible for the metabolism of a number of therapeutic agents such as the anticonvulsant drug S-mephenytoin, omeprazole, proguanil, certain barbiturates, diazepam, propranolol, citalopram and imipramine.
Gene Name:
CYP2C19
Uniprot ID:
P33261
Molecular weight:
55944.565
References
  1. Preissner S, Kroll K, Dunkel M, Senger C, Goldsobel G, Kuzman D, Guenther S, Winnenburg R, Schroeder M, Preissner R: SuperCYP: a comprehensive database on Cytochrome P450 enzymes including a tool for analysis of CYP-drug interactions. Nucleic Acids Res. 2010 Jan;38(Database issue):D237-43. Epub 2009 Nov 24. [19934256 ]
General function:
Involved in monooxygenase activity
Specific function:
Cytochromes P450 are a group of heme-thiolate monooxygenases. In liver microsomes, this enzyme is involved in an NADPH-dependent electron transport pathway. It oxidizes a variety of structurally unrelated compounds, including steroids, fatty acids, and xenobiotics.
Gene Name:
CYP2C18
Uniprot ID:
P33260
Molecular weight:
55710.075
References
  1. Preissner S, Kroll K, Dunkel M, Senger C, Goldsobel G, Kuzman D, Guenther S, Winnenburg R, Schroeder M, Preissner R: SuperCYP: a comprehensive database on Cytochrome P450 enzymes including a tool for analysis of CYP-drug interactions. Nucleic Acids Res. 2010 Jan;38(Database issue):D237-43. Epub 2009 Nov 24. [19934256 ]
General function:
Involved in monooxygenase activity
Specific function:
Cytochromes P450 are a group of heme-thiolate monooxygenases. In liver microsomes, this enzyme is involved in an NADPH-dependent electron transport pathway. It oxidizes a variety of structurally unrelated compounds, including steroids, fatty acids, and xenobiotics. Acts as a 1,4-cineole 2-exo-monooxygenase.
Gene Name:
CYP2B6
Uniprot ID:
P20813
Molecular weight:
56277.81
References
  1. Zhou SF, Zhou ZW, Yang LP, Cai JP: Substrates, inducers, inhibitors and structure-activity relationships of human Cytochrome P450 2C9 and implications in drug development. Curr Med Chem. 2009;16(27):3480-675. Epub 2009 Sep 1. [19515014 ]
General function:
Involved in monooxygenase activity
Specific function:
Cytochromes P450 are a group of heme-thiolate monooxygenases. In liver microsomes, this enzyme is involved in an NADPH-dependent electron transport pathway. It oxidizes a variety of structurally unrelated compounds, including steroids, fatty acids, and xenobiotics.
Gene Name:
CYP3A5
Uniprot ID:
P20815
Molecular weight:
57108.065
References
  1. Zhou SF, Zhou ZW, Yang LP, Cai JP: Substrates, inducers, inhibitors and structure-activity relationships of human Cytochrome P450 2C9 and implications in drug development. Curr Med Chem. 2009;16(27):3480-675. Epub 2009 Sep 1. [19515014 ]
General function:
Involved in monooxygenase activity
Specific function:
Cytochromes P450 are a group of heme-thiolate monooxygenases. In liver microsomes, this enzyme is involved in an NADPH-dependent electron transport pathway. It oxidizes a variety of structurally unrelated compounds, including steroids, fatty acids, and xenobiotics. Most active in catalyzing 2-hydroxylation. Caffeine is metabolized primarily by cytochrome CYP1A2 in the liver through an initial N3-demethylation. Also acts in the metabolism of aflatoxin B1 and acetaminophen. Participates in the bioactivation of carcinogenic aromatic and heterocyclic amines. Catalizes the N-hydroxylation of heterocyclic amines and the O-deethylation of phenacetin.
Gene Name:
CYP1A2
Uniprot ID:
P05177
Molecular weight:
58406.915
References
  1. Preissner S, Kroll K, Dunkel M, Senger C, Goldsobel G, Kuzman D, Guenther S, Winnenburg R, Schroeder M, Preissner R: SuperCYP: a comprehensive database on Cytochrome P450 enzymes including a tool for analysis of CYP-drug interactions. Nucleic Acids Res. 2010 Jan;38(Database issue):D237-43. Epub 2009 Nov 24. [19934256 ]
General function:
Involved in monooxygenase activity
Specific function:
Cytochromes P450 are a group of heme-thiolate monooxygenases. In liver microsomes, this enzyme is involved in an NADPH-dependent electron transport pathway. It oxidizes a variety of structurally unrelated compounds, including steroids, fatty acids, and xenobiotics. In the epoxidation of arachidonic acid it generates only 14,15- and 11,12-cis-epoxyeicosatrienoic acids. It is the principal enzyme responsible for the metabolism the anti-cancer drug paclitaxel (taxol).
Gene Name:
CYP2C8
Uniprot ID:
P10632
Molecular weight:
55824.275
References
  1. Preissner S, Kroll K, Dunkel M, Senger C, Goldsobel G, Kuzman D, Guenther S, Winnenburg R, Schroeder M, Preissner R: SuperCYP: a comprehensive database on Cytochrome P450 enzymes including a tool for analysis of CYP-drug interactions. Nucleic Acids Res. 2010 Jan;38(Database issue):D237-43. Epub 2009 Nov 24. [19934256 ]
General function:
Involved in monooxygenase activity
Specific function:
Exhibits a high coumarin 7-hydroxylase activity. Can act in the hydroxylation of the anti-cancer drugs cyclophosphamide and ifosphamide. Competent in the metabolic activation of aflatoxin B1. Constitutes the major nicotine C-oxidase. Acts as a 1,4-cineole 2-exo-monooxygenase. Possesses low phenacetin O-deethylation activity.
Gene Name:
CYP2A6
Uniprot ID:
P11509
Molecular weight:
56517.005
References
  1. Zhou SF, Zhou ZW, Yang LP, Cai JP: Substrates, inducers, inhibitors and structure-activity relationships of human Cytochrome P450 2C9 and implications in drug development. Curr Med Chem. 2009;16(27):3480-675. Epub 2009 Sep 1. [19515014 ]
  2. Preissner S, Kroll K, Dunkel M, Senger C, Goldsobel G, Kuzman D, Guenther S, Winnenburg R, Schroeder M, Preissner R: SuperCYP: a comprehensive database on Cytochrome P450 enzymes including a tool for analysis of CYP-drug interactions. Nucleic Acids Res. 2010 Jan;38(Database issue):D237-43. Epub 2009 Nov 24. [19934256 ]
General function:
Involved in acyl-CoA dehydrogenase activity
Specific function:
Has greatest activity toward short branched chain acyl-CoA derivative such as (s)-2-methylbutyryl-CoA, isobutyryl-CoA, and 2-methylhexanoyl-CoA as well as toward short straight chain acyl-CoAs such as butyryl-CoA and hexanoyl-CoA. Can use valproyl-CoA as substrate and may play a role in controlling the metabolic flux of valproic acid in the development of toxicity of this agent.
Gene Name:
ACADSB
Uniprot ID:
P45954
Molecular weight:
47485.035
References
  1. Ito M, Ikeda Y, Arnez JG, Finocchiaro G, Tanaka K: The enzymatic basis for the metabolism and inhibitory effects of valproic acid: dehydrogenation of valproyl-CoA by 2-methyl-branched-chain acyl-CoA dehydrogenase. Biochim Biophys Acta. 1990 May 16;1034(2):213-8. [2112956 ]
  2. Bazinet RP, Weis MT, Rapoport SI, Rosenberger TA: Valproic acid selectively inhibits conversion of arachidonic acid to arachidonoyl-CoA by brain microsomal long-chain fatty acyl-CoA synthetases: relevance to bipolar disorder. Psychopharmacology (Berl). 2006 Jan;184(1):122-9. Epub 2005 Dec 13. [16344985 ]
General function:
Involved in histone deacetylase activity
Specific function:
Isoform 3 lacks active site residues and therefore is catalytically inactive. Represses MEF2-dependent transcription by recruiting HDAC1 and/or HDAC3. Seems to inhibit skeletal myogenesis and to be involved in heart development. Protects neurons from apoptosis, both by inhibiting JUN phosphorylation by MAPK10 and by repressing JUN transcription via HDAC1 recruitment to JUN promoter
Gene Name:
HDAC9
Uniprot ID:
Q9UKV0
Molecular weight:
111296.3
References
  1. Ylisastigui L, Archin NM, Lehrman G, Bosch RJ, Margolis DM: Coaxing HIV-1 from resting CD4 T cells: histone deacetylase inhibition allows latent viral expression. AIDS. 2004 May 21;18(8):1101-8. [15166525 ]
  2. Michaelis M, Kohler N, Reinisch A, Eikel D, Gravemann U, Doerr HW, Nau H, Cinatl J Jr: Increased human cytomegalovirus replication in fibroblasts after treatment with therapeutical plasma concentrations of valproic acid. Biochem Pharmacol. 2004 Aug 1;68(3):531-8. [15242819 ]
  3. Kanai H, Sawa A, Chen RW, Leeds P, Chuang DM: Valproic acid inhibits histone deacetylase activity and suppresses excitotoxicity-induced GAPDH nuclear accumulation and apoptotic death in neurons. Pharmacogenomics J. 2004;4(5):336-44. [15289798 ]
  4. Stockhausen MT, Sjolund J, Manetopoulos C, Axelson H: Effects of the histone deacetylase inhibitor valproic acid on Notch signalling in human neuroblastoma cells. Br J Cancer. 2005 Feb 28;92(4):751-9. [15685243 ]
  5. Beutler AS, Li S, Nicol R, Walsh MJ: Carbamazepine is an inhibitor of histone deacetylases. Life Sci. 2005 May 13;76(26):3107-15. [15850602 ]
  6. Rosenberg G: The mechanisms of action of valproate in neuropsychiatric disorders: can we see the forest for the trees? Cell Mol Life Sci. 2007 Aug;64(16):2090-103. [17514356 ]
  7. Kawano T, Akiyama M, Agawa-Ohta M, Mikami-Terao Y, Iwase S, Yanagisawa T, Ida H, Agata N, Yamada H: Histone deacetylase inhibitors valproic acid and depsipeptide sensitize retinoblastoma cells to radiotherapy by increasing H2AX phosphorylation and p53 acetylation-phosphorylation. Int J Oncol. 2010 Oct;37(4):787-95. [20811699 ]

Transporters

General function:
Involved in transmembrane transport
Specific function:
Proton-linked monocarboxylate transporter. Catalyzes the rapid transport across the plasma membrane of many monocarboxylates such as lactate, pyruvate, branched-chain oxo acids derived from leucine, valine and isoleucine, and the ketone bodies acetoacetate, beta-hydroxybutyrate and acetate
Gene Name:
SLC16A1
Uniprot ID:
P53985
Molecular weight:
53957.7
References
  1. Tamai I, Sai Y, Ono A, Kido Y, Yabuuchi H, Takanaga H, Satoh E, Ogihara T, Amano O, Izeki S, Tsuji A: Immunohistochemical and functional characterization of pH-dependent intestinal absorption of weak organic acids by the monocarboxylic acid transporter MCT1. J Pharm Pharmacol. 1999 Oct;51(10):1113-21. [10579682 ]
General function:
Involved in ion transmembrane transporter activity
Specific function:
Sodium-ion dependent, high affinity carnitine transporter. Involved in the active cellular uptake of carnitine. Transports one sodium ion with one molecule of carnitine. Also transports organic cations such as tetraethylammonium (TEA) without the involvement of sodium. Also relative uptake activity ratio of carnitine to TEA is 11.3
Gene Name:
SLC22A5
Uniprot ID:
O76082
Molecular weight:
62751.1
References
  1. Ohashi R, Tamai I, Yabuuchi H, Nezu JI, Oku A, Sai Y, Shimane M, Tsuji A: Na(+)-dependent carnitine transport by organic cation transporter (OCTN2): its pharmacological and toxicological relevance. J Pharmacol Exp Ther. 1999 Nov;291(2):778-84. [10525100 ]
General function:
Involved in ion transmembrane transporter activity
Specific function:
Involved in the renal elimination of endogenous and exogenous organic anions. Functions as organic anion exchanger when the uptake of one molecule of organic anion is coupled with an efflux of one molecule of endogenous dicarboxylic acid (glutarate, ketoglutarate, etc). Mediates the sodium-independent uptake of 2,3-dimercapto-1-propanesulfonic acid (DMPS). Mediates the sodium-independent uptake of p- aminohippurate (PAH), ochratoxin (OTA), acyclovir (ACV), 3'-azido- 3-'deoxythymidine (AZT), cimetidine (CMD), 2,4-dichloro- phenoxyacetate (2,4-D), hippurate (HA), indoleacetate (IA), indoxyl sulfate (IS) and 3-carboxy-4-methyl-5-propyl-2- furanpropionate (CMPF), cidofovir, adefovir, 9-(2- phosphonylmethoxyethyl) guanine (PMEG), 9-(2- phosphonylmethoxyethyl) diaminopurine (PMEDAP) and edaravone sulfate. PAH uptake is inhibited by p- chloromercuribenzenesulphonate (PCMBS), diethyl pyrocarbonate (DEPC), sulindac, diclofenac, carprofen, glutarate and okadaic acid. PAH uptake is inhibited by benzothiazolylcysteine (BTC), S-chlorotrifluoroethylcysteine (CTFC), cysteine S-conjugates S-dichlorovinylcysteine (DCVC), furosemide, steviol, phorbol 12-myristate 13-acetate (PMA), calcium ionophore A23187, benzylpenicillin, furosemide, indomethacin, bumetamide, losartan, probenecid, phenol red, urate, and alpha-ketoglutarate
Gene Name:
SLC22A6
Uniprot ID:
Q4U2R8
Molecular weight:
61815.8
References
  1. Sekine T, Watanabe N, Hosoyamada M, Kanai Y, Endou H: Expression cloning and characterization of a novel multispecific organic anion transporter. J Biol Chem. 1997 Jul 25;272(30):18526-9. [9228014 ]
General function:
Involved in transmembrane transport
Specific function:
Mediates sodium-independent multispecific organic anion transport. Transport of prostaglandin E2, prostaglandin F2, tetracycline, bumetanide, estrone sulfate, glutarate, dehydroepiandrosterone sulfate, allopurinol, 5-fluorouracil, paclitaxel, L-ascorbic acid, salicylate, ethotrexate, and alpha- ketoglutarate
Gene Name:
SLC22A7
Uniprot ID:
Q9Y694
Molecular weight:
60025.0
References
  1. Kobayashi Y, Ohshiro N, Shibusawa A, Sasaki T, Tokuyama S, Sekine T, Endou H, Yamamoto T: Isolation, characterization and differential gene expression of multispecific organic anion transporter 2 in mice. Mol Pharmacol. 2002 Jul;62(1):7-14. [12065749 ]