Record Information
Version2.0
Creation Date2009-07-05 03:34:13 UTC
Update Date2014-12-24 20:25:43 UTC
Accession NumberT3D2575
Identification
Common NameTramadol
ClassSmall Molecule
DescriptionA narcotic analgesic proposed for moderate to severe pain. It may be habituating. Tramadol is also prepared as a variable release capsules, marketed under the brand name ConZip. For example, a 150 mg capsule will contain 37.5 mg of the immediate release form and 112.5 mg of the extended release form. Tramadol is only found in individuals that have used or taken this drug. It is a narcotic analgesic proposed for moderate to severe pain. It may be habituating. Tramadol and its O-desmethyl metabolite (M1) are selective, weak OP3-receptor agonists. Opiate receptors are coupled with G-protein receptors and function as both positive and negative regulators of synaptic transmission via G-proteins that activate effector proteins. As the effector system is adenylate cyclase and cAMP located at the inner surface of the plasma membrane, opioids decrease intracellular cAMP by inhibiting adenylate cyclase. Subsequently, the release of nociceptive neurotransmitters such as substance P, GABA, dopamine, acetylcholine and noradrenaline is inhibited. The analgesic properties of Tramadol can be attributed to norepinephrine and serotonin reuptake blockade in the CNS, which inhibits pain transmission in the spinal cord. The (+) enantiomer has higher affinity for the OP3 receptor and preferentially inhibits serotonin uptake and enhances serotonin release. The (-) enantiomer preferentially inhibits norepinephrine reuptake by stimulating alpha(2)-adrenergic receptors.
Compound Type
  • Amine
  • Analgesic
  • Analgesic, Opioid
  • Drug
  • Ether
  • Metabolite
  • Narcotic
  • Organic Compound
  • Synthetic Compound
Chemical Structure
Thumb
Synonyms
Synonym
(+)-Tramadol
(+)-trans-2-(Dimethylaminomethyl)-1-(m-methoxyphenyl)cyclohexanol
ConZip
Durela
Ralivia
Rybix
Ryzolt
Tramal
Tridural
Ultram
Zytram xl
Chemical FormulaC16H25NO2
Average Molecular Mass263.375 g/mol
Monoisotopic Mass263.189 g/mol
CAS Registry Number27203-92-5
IUPAC Name(1R,2R)-2-[(dimethylamino)methyl]-1-(3-methoxyphenyl)cyclohexan-1-ol
Traditional Nametramadol
SMILES[H][C@]1(CN(C)C)CCCC[C@]1(O)C1=CC(OC)=CC=C1
InChI IdentifierInChI=1S/C16H25NO2/c1-17(2)12-14-7-4-5-10-16(14,18)13-8-6-9-15(11-13)19-3/h6,8-9,11,14,18H,4-5,7,10,12H2,1-3H3/t14-,16+/m1/s1
InChI KeyInChIKey=TVYLLZQTGLZFBW-ZBFHGGJFSA-N
Chemical Taxonomy
Description belongs to the class of organic compounds known as anisoles. These are organic compounds containing a methoxybenzene or a derivative thereof.
KingdomOrganic compounds
Super ClassBenzenoids
ClassPhenol ethers
Sub ClassAnisoles
Direct ParentAnisoles
Alternative Parents
Substituents
  • Phenoxy compound
  • Anisole
  • Methoxybenzene
  • Alkyl aryl ether
  • Cyclohexanol
  • Aralkylamine
  • Monocyclic benzene moiety
  • Tertiary alcohol
  • Cyclic alcohol
  • Tertiary aliphatic amine
  • Tertiary amine
  • Ether
  • Organooxygen compound
  • Organonitrogen compound
  • Organopnictogen compound
  • Alcohol
  • Organic oxygen compound
  • Amine
  • Organic nitrogen compound
  • Hydrocarbon derivative
  • Aromatic homomonocyclic compound
Molecular FrameworkAromatic homomonocyclic compounds
External Descriptors
  • 2-[(dimethylamino)methyl]-1-(3-methoxyphenyl)cyclohexanol (CHEBI:75725 )
Biological Properties
StatusDetected and Not Quantified
OriginExogenous
Cellular Locations
  • Membrane
Biofluid LocationsNot Available
Tissue LocationsNot Available
PathwaysNot Available
Applications
Biological Roles
Chemical RolesNot Available
Physical Properties
StateSolid
AppearanceSolid (1).
Experimental Properties
PropertyValue
Melting Point180-181°C
Boiling PointNot Available
SolubilitySoluble
LogP2.4
Predicted Properties
PropertyValueSource
Water Solubility0.75 g/LALOGPS
logP2.71ALOGPS
logP2.45ChemAxon
logS-2.6ALOGPS
pKa (Strongest Acidic)13.8ChemAxon
pKa (Strongest Basic)9.23ChemAxon
Physiological Charge1ChemAxon
Hydrogen Acceptor Count3ChemAxon
Hydrogen Donor Count1ChemAxon
Polar Surface Area32.7 ŲChemAxon
Rotatable Bond Count4ChemAxon
Refractivity78.27 m³·mol⁻¹ChemAxon
Polarizability30.45 ųChemAxon
Number of Rings2ChemAxon
Bioavailability1ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
Spectra
Spectra
Spectrum TypeDescriptionSplash KeyDeposition DateView
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positivesplash10-0a4i-9650000000-250d842ef062333281702017-09-01View Spectrum
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (1 TMS) - 70eV, Positivesplash10-05fr-5193000000-dd2e84f70a47d0634c432017-10-06View Spectrum
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, PositiveNot Available2021-10-12View Spectrum
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, PositiveNot Available2021-10-12View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-qTof , Positivesplash10-03di-0090000000-1550dc2447717d7d87282017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QTOF , positivesplash10-03di-0090000000-7850be0ba78033f1f6772017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QTOF , positivesplash10-03di-0090000000-62a3c5cb6717bff20e2c2017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QTOF , positivesplash10-05fs-0930000000-b8297a71c45e9630f6c02017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QTOF , positivesplash10-05fr-0900000000-f650c49b70db20869d0f2017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QTOF , positivesplash10-0adl-0900000000-b17dfc32e2eb57efaf422017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT , positivesplash10-0002-0090000000-c35bec467cfec28511fb2017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT , positivesplash10-03di-1090000000-9ca08dcdc5a2027bcb032017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT , positivesplash10-0a4i-9030000000-469467d2583e7202d89f2017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT , positivesplash10-0a4i-9000000000-89f055b497c88cdc5e792017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT , positivesplash10-0a4i-9000000000-1922068301c6d3b4f4572017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT , positivesplash10-0a4i-9000000000-1922068301c6d3b4f4572017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT , positivesplash10-0a4i-9000000000-5a9396f20ce15b9c08ba2017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT , positivesplash10-03di-1090000000-e040861e9fa18a8f44a52017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT , positivesplash10-0a4i-9030000000-fa1522b6a491e6da41c92017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT , positivesplash10-0a4i-9000000000-8ab0ebc3ceff7c5e5ce52017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT , positivesplash10-0a4i-9000000000-7645dc9b29d8b28674952017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT , positivesplash10-0a4i-9000000000-70cad0a31ff2d57bab812017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT , positivesplash10-0a4i-9000000000-bf1b2c15c6511355c9e12017-09-14View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-01ot-0090000000-7fe9a41fb060355ba0c02016-08-02View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-0hft-1190000000-8c3c0de6df7ced23802a2016-08-02View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-0pbc-9120000000-4f0e74f6721de4ccf0672016-08-02View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-03di-0090000000-24bef5bd2510914bee832016-08-03View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-03di-1490000000-3314217686d7d48bff0d2016-08-03View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-0a4l-9380000000-76c818434cc5aeed5aca2016-08-03View Spectrum
MSMass Spectrum (Electron Ionization)splash10-0a4i-9010000000-ffea37e400f0860f2e7f2014-09-20View Spectrum
Toxicity Profile
Route of ExposureInhalation. Racemic tramadol is rapidly and almost completely absorbed after oral administration. The mean absolute bioavailability of a 100 mg oral dose is approximately 75%. The mean peak plasma concentration of racemic tramadol and M1 occurs at two and three hours, respectively, after administration in healthy adults.
Mechanism of ToxicityTramadol and its O-desmethyl metabolite (M1) are selective, weak OP3-receptor agonists. Opiate receptors are coupled with G-protein receptors and function as both positive and negative regulators of synaptic transmission via G-proteins that activate effector proteins. As the effector system is adenylate cyclase and cAMP located at the inner surface of the plasma membrane, opioids decrease intracellular cAMP by inhibiting adenylate cyclase. Subsequently, the release of nociceptive neurotransmitters such as substance P, GABA, dopamine, acetylcholine and noradrenaline is inhibited. The analgesic properties of Tramadol can be attributed to norepinephrine and serotonin reuptake blockade in the CNS, which inhibits pain transmission in the spinal cord. The (+) enantiomer has higher affinity for the OP3 receptor and preferentially inhibits serotonin uptake and enhances serotonin release. The (-) enantiomer preferentially inhibits norepinephrine reuptake by stimulating alpha(2)-adrenergic receptors.
MetabolismHepatic. The major metabolic pathways appear to be N- and O- demethylation and glucuronidation or sulfation in the liver. One metabolite (O-desmethyltramadol, denoted M1) is pharmacologically active in animal models. CYP3A4 and CYP2B6 facilitates the biotransformation of tramadol to N-desmethyl-tramadol. CYP2D6 facilitates the biotransformation of tramadol to O-desmethyl-tramadol. Racemic tramadol is rapidly and almost completely absorbed after oral administration. The mean absolute bioavailability of a 100 mg oral dose is approximately 75%.The mean peak plasma concentration of racemic tramadol and M1 occurs at two and three hours, respectively, after administration in healthy adults. Tramadol undergoes hepatic metabolism via the cytochrome P450 isozyme CYP2D6, being O- and N-demethylated to five different metabolites. Of these, M1 (O-Desmethyltramadol) is the most significant since it has 200 times the affinity of (+)-tramadol, and furthermore has an elimination half-life of nine hours, compared with six hours for tramadol itself. In the 6% of the population that have slow CYP2D6 activity, there is therefore a slightly reduced analgesic effect. Phase II hepatic metabolism renders the metabolites water-soluble, which are excreted by the kidneys. Thus, reduced doses may be used in renal and hepatic impairment (1, 9). Route of Elimination: Tramadol is eliminated primarily through metabolism by the liver and the metabolites are excreted primarily by the kidneys. Approximately 30% of the dose is excreted in the urine as unchanged drug, whereas 60% of the dose is excreted as metabolites. Half Life: Tramadol and its metabolites are excreted primarily in the urine with observed plasma half-lives of 6.3 and 7.4 hours for tramadol and M1, respectively.
Toxicity ValuesLD50: 300-350 mg/kg (Oral, Rat) (7)
Lethal DoseNot Available
Carcinogenicity (IARC Classification)No indication of carcinogenicity to humans (not listed by IARC).
Uses/SourcesIndicated in the treatment of moderate to severe pain. Consider for those prone to constipation or respiratory depression. Tramadol is used to treat postoperative, dental, cancer, and acute musculosketetal pain and as an adjuvant to NSAID therapy in patients with osteoarthritis (1).
Minimum Risk LevelNot Available
Health EffectsSerious potential consequences of overdosage are respiratory depression, lethargy, coma, seizure, cardiac arrest and death. The respiratory depressant effects include carbon dioxide retention and secondary elevation of cerebrospinal fluid pressure, and may be markedly exaggerated in these patients (RxList, A308). Medical problems can include congested lungs, liver disease, tetanus, infection of the heart valves, skin abscesses, anemia and pneumonia. Death can occur from overdose.
SymptomsOverdose symptoms of a tramadol overdose may include drowsiness, shallow breathing, slow heartbeat, extreme weakness, cold or clammy skin, feeling light-headed, fainting, or coma. (10)
TreatmentIn treating an overdose, primary attention should be given to maintaining adequate ventilation along with general supportive treatment. While naloxone will reverse some, but not all, symptoms caused by overdosage with ULTRAM, the risk of seizures is also increased with naloxone administration. (11)
Normal Concentrations
Not Available
Abnormal Concentrations
Not Available
DrugBank IDDB00193
HMDB IDHMDB14339
PubChem Compound ID33741
ChEMBL IDCHEMBL1237044
ChemSpider ID31105
KEGG IDC07153
UniProt IDNot Available
OMIM ID
ChEBI ID238661
BioCyc IDCYCLOHEXANOL
CTD IDNot Available
Stitch IDTramadol
PDB IDNot Available
ACToR IDNot Available
Wikipedia LinkTramadol
References
Synthesis Reference

Wolfgang Reimann, “Combination preparation containing tramadol and a calcium channel antagonist.” U.S. Patent US5929122, issued March, 1993.

MSDSLink
General References
  1. Wishart DS, Knox C, Guo AC, Cheng D, Shrivastava S, Tzur D, Gautam B, Hassanali M: DrugBank: a knowledgebase for drugs, drug actions and drug targets. Nucleic Acids Res. 2008 Jan;36(Database issue):D901-6. Epub 2007 Nov 29. [18048412 ]
  2. Dayer P, Desmeules J, Collart L: [Pharmacology of tramadol]. Drugs. 1997;53 Suppl 2:18-24. [9190321 ]
  3. Harati Y, Gooch C, Swenson M, Edelman S, Greene D, Raskin P, Donofrio P, Cornblath D, Sachdeo R, Siu CO, Kamin M: Double-blind randomized trial of tramadol for the treatment of the pain of diabetic neuropathy. Neurology. 1998 Jun;50(6):1842-6. [9633738 ]
  4. Harati Y, Gooch C, Swenson M, Edelman SV, Greene D, Raskin P, Donofrio P, Cornblath D, Olson WH, Kamin M: Maintenance of the long-term effectiveness of tramadol in treatment of the pain of diabetic neuropathy. J Diabetes Complications. 2000 Mar-Apr;14(2):65-70. [10959067 ]
  5. Gobel H, Stadler T: [Treatment of post-herpes zoster pain with tramadol. Results of an open pilot study versus clomipramine with or without levomepromazine]. Drugs. 1997;53 Suppl 2:34-9. [9190323 ]
  6. Boureau F, Legallicier P, Kabir-Ahmadi M: Tramadol in post-herpetic neuralgia: a randomized, double-blind, placebo-controlled trial. Pain. 2003 Jul;104(1-2):323-31. [12855342 ]
  7. Matthiesen T, Wohrmann T, Coogan TP, Uragg H: The experimental toxicology of tramadol: an overview. Toxicol Lett. 1998 Mar 16;95(1):63-71. [9650647 ]
  8. FDA label
  9. Wikipedia. Tramadol. Last Updated 8 August 2009. [Link]
  10. Drugs.com [Link]
  11. RxList: The Internet Drug Index (2009). [Link]
Gene Regulation
Up-Regulated GenesNot Available
Down-Regulated GenesNot Available

Targets

General Function:
Voltage-gated calcium channel activity
Specific Function:
Receptor for endogenous opioids such as beta-endorphin and endomorphin. Receptor for natural and synthetic opioids including morphine, heroin, DAMGO, fentanyl, etorphine, buprenorphin and methadone. Agonist binding to the receptor induces coupling to an inactive GDP-bound heterotrimeric G-protein complex and subsequent exchange of GDP for GTP in the G-protein alpha subunit leading to dissociation of the G-protein complex with the free GTP-bound G-protein alpha and the G-protein beta-gamma dimer activating downstream cellular effectors. The agonist- and cell type-specific activity is predominantly coupled to pertussis toxin-sensitive G(i) and G(o) G alpha proteins, GNAI1, GNAI2, GNAI3 and GNAO1 isoforms Alpha-1 and Alpha-2, and to a lesser extend to pertussis toxin-insensitive G alpha proteins GNAZ and GNA15. They mediate an array of downstream cellular responses, including inhibition of adenylate cyclase activity and both N-type and L-type calcium channels, activation of inward rectifying potassium channels, mitogen-activated protein kinase (MAPK), phospholipase C (PLC), phosphoinositide/protein kinase (PKC), phosphoinositide 3-kinase (PI3K) and regulation of NF-kappa-B. Also couples to adenylate cyclase stimulatory G alpha proteins. The selective temporal coupling to G-proteins and subsequent signaling can be regulated by RGSZ proteins, such as RGS9, RGS17 and RGS4. Phosphorylation by members of the GPRK subfamily of Ser/Thr protein kinases and association with beta-arrestins is involved in short-term receptor desensitization. Beta-arrestins associate with the GPRK-phosphorylated receptor and uncouple it from the G-protein thus terminating signal transduction. The phosphorylated receptor is internalized through endocytosis via clathrin-coated pits which involves beta-arrestins. The activation of the ERK pathway occurs either in a G-protein-dependent or a beta-arrestin-dependent manner and is regulated by agonist-specific receptor phosphorylation. Acts as a class A G-protein coupled receptor (GPCR) which dissociates from beta-arrestin at or near the plasma membrane and undergoes rapid recycling. Receptor down-regulation pathways are varying with the agonist and occur dependent or independent of G-protein coupling. Endogenous ligands induce rapid desensitization, endocytosis and recycling whereas morphine induces only low desensitization and endocytosis. Heterooligomerization with other GPCRs can modulate agonist binding, signaling and trafficking properties. Involved in neurogenesis. Isoform 12 couples to GNAS and is proposed to be involved in excitatory effects. Isoform 16 and isoform 17 do not bind agonists but may act through oligomerization with binding-competent OPRM1 isoforms and reduce their ligand binding activity.
Gene Name:
OPRM1
Uniprot ID:
P35372
Molecular Weight:
44778.855 Da
References
  1. Chen X, Ji ZL, Chen YZ: TTD: Therapeutic Target Database. Nucleic Acids Res. 2002 Jan 1;30(1):412-5. [11752352 ]
  2. Gillen C, Haurand M, Kobelt DJ, Wnendt S: Affinity, potency and efficacy of tramadol and its metabolites at the cloned human mu-opioid receptor. Naunyn Schmiedebergs Arch Pharmacol. 2000 Aug;362(2):116-21. [10961373 ]
  3. Potschka H, Friderichs E, Loscher W: Anticonvulsant and proconvulsant effects of tramadol, its enantiomers and its M1 metabolite in the rat kindling model of epilepsy. Br J Pharmacol. 2000 Sep;131(2):203-12. [10991912 ]
  4. Raffa RB, Friderichs E, Reimann W, Shank RP, Codd EE, Vaught JL: Opioid and nonopioid components independently contribute to the mechanism of action of tramadol, an 'atypical' opioid analgesic. J Pharmacol Exp Ther. 1992 Jan;260(1):275-85. [1309873 ]
  5. Grond S, Sablotzki A: Clinical pharmacology of tramadol. Clin Pharmacokinet. 2004;43(13):879-923. [15509185 ]
  6. Ide S, Minami M, Ishihara K, Uhl GR, Sora I, Ikeda K: Mu opioid receptor-dependent and independent components in effects of tramadol. Neuropharmacology. 2006 Sep;51(3):651-8. Epub 2006 Jun 21. [16793069 ]
General Function:
Serotonin receptor activity
Specific Function:
G-protein coupled receptor for 5-hydroxytryptamine (serotonin). Also functions as a receptor for various drugs and psychoactive substances, including ergot alkaloid derivatives, 1-2,5,-dimethoxy-4-iodophenyl-2-aminopropane (DOI) and lysergic acid diethylamide (LSD). Ligand binding causes a conformation change that triggers signaling via guanine nucleotide-binding proteins (G proteins) and modulates the activity of down-stream effectors. Beta-arrestin family members inhibit signaling via G proteins and mediate activation of alternative signaling pathways. Signaling activates a phosphatidylinositol-calcium second messenger system that modulates the activity of phosphatidylinositol 3-kinase and down-stream signaling cascades and promotes the release of Ca(2+) ions from intracellular stores. Regulates neuronal activity via the activation of short transient receptor potential calcium channels in the brain, and thereby modulates the activation of pro-opiomelacortin neurons and the release of CRH that then regulates the release of corticosterone. Plays a role in the regulation of appetite and eating behavior, responses to anxiogenic stimuli and stress. Plays a role in insulin sensitivity and glucose homeostasis.
Gene Name:
HTR2C
Uniprot ID:
P28335
Molecular Weight:
51820.705 Da
References
  1. Ogata J, Minami K, Uezono Y, Okamoto T, Shiraishi M, Shigematsu A, Ueta Y: The inhibitory effects of tramadol on 5-hydroxytryptamine type 2C receptors expressed in Xenopus oocytes. Anesth Analg. 2004 May;98(5):1401-6, table of contents. [15105221 ]
  2. Horishita T, Minami K, Uezono Y, Shiraishi M, Ogata J, Okamoto T, Shigematsu A: The tramadol metabolite, O-desmethyl tramadol, inhibits 5-hydroxytryptamine type 2C receptors expressed in Xenopus Oocytes. Pharmacology. 2006;77(2):93-9. Epub 2006 May 5. [16679816 ]
General Function:
Receptor activity
Specific Function:
The muscarinic acetylcholine receptor mediates various cellular responses, including inhibition of adenylate cyclase, breakdown of phosphoinositides and modulation of potassium channels through the action of G proteins. Primary transducing effect is Pi turnover.
Gene Name:
CHRM3
Uniprot ID:
P20309
Molecular Weight:
66127.445 Da
References
  1. Shiraishi M, Minami K, Uezono Y, Yanagihara N, Shigematsu A: Inhibition by tramadol of muscarinic receptor-induced responses in cultured adrenal medullary cells and in Xenopus laevis oocytes expressing cloned M1 receptors. J Pharmacol Exp Ther. 2001 Oct;299(1):255-60. [11561087 ]
  2. Shiga Y, Minami K, Shiraishi M, Uezono Y, Murasaki O, Kaibara M, Shigematsu A: The inhibitory effects of tramadol on muscarinic receptor-induced responses in Xenopus oocytes expressing cloned M(3) receptors. Anesth Analg. 2002 Nov;95(5):1269-73, table of contents. [12401609 ]
General Function:
Norepinephrine:sodium symporter activity
Specific Function:
Amine transporter. Terminates the action of noradrenaline by its high affinity sodium-dependent reuptake into presynaptic terminals.
Gene Name:
SLC6A2
Uniprot ID:
P23975
Molecular Weight:
69331.42 Da
References
  1. Chen X, Ji ZL, Chen YZ: TTD: Therapeutic Target Database. Nucleic Acids Res. 2002 Jan 1;30(1):412-5. [11752352 ]
  2. Sagata K, Minami K, Yanagihara N, Shiraishi M, Toyohira Y, Ueno S, Shigematsu A: Tramadol inhibits norepinephrine transporter function at desipramine-binding sites in cultured bovine adrenal medullary cells. Anesth Analg. 2002 Apr;94(4):901-6, table of contents. [11916794 ]
General Function:
Serotonin:sodium symporter activity
Specific Function:
Serotonin transporter whose primary function in the central nervous system involves the regulation of serotonergic signaling via transport of serotonin molecules from the synaptic cleft back into the pre-synaptic terminal for re-utilization. Plays a key role in mediating regulation of the availability of serotonin to other receptors of serotonergic systems. Terminates the action of serotonin and recycles it in a sodium-dependent manner.
Gene Name:
SLC6A4
Uniprot ID:
P31645
Molecular Weight:
70324.165 Da
References
  1. Barann M, Urban B, Stamer U, Dorner Z, Bonisch H, Bruss M: Effects of tramadol and O-demethyl-tramadol on human 5-HT reuptake carriers and human 5-HT3A receptors: a possible mechanism for tramadol-induced early emesis. Eur J Pharmacol. 2006 Feb 15;531(1-3):54-8. Epub 2006 Jan 19. [16427041 ]
  2. Driessen B, Reimann W: Interaction of the central analgesic, tramadol, with the uptake and release of 5-hydroxytryptamine in the rat brain in vitro. Br J Pharmacol. 1992 Jan;105(1):147-51. [1596676 ]
General Function:
Not Available
Specific Function:
Not Available
Gene Name:
CHRNA7
Uniprot ID:
Q693P7
Molecular Weight:
2987.635 Da
References
  1. Shiraishi M, Minami K, Uezono Y, Yanagihara N, Shigematsu A, Shibuya I: Inhibitory effects of tramadol on nicotinic acetylcholine receptors in adrenal chromaffin cells and in Xenopus oocytes expressing alpha 7 receptors. Br J Pharmacol. 2002 May;136(2):207-16. [12010769 ]
General Function:
Opioid receptor activity
Specific Function:
G-protein coupled receptor that functions as receptor for endogenous enkephalins and for a subset of other opioids. Ligand binding causes a conformation change that triggers signaling via guanine nucleotide-binding proteins (G proteins) and modulates the activity of down-stream effectors, such as adenylate cyclase. Signaling leads to the inhibition of adenylate cyclase activity. Inhibits neurotransmitter release by reducing calcium ion currents and increasing potassium ion conductance. Plays a role in the perception of pain and in opiate-mediated analgesia. Plays a role in developing analgesic tolerance to morphine.
Gene Name:
OPRD1
Uniprot ID:
P41143
Molecular Weight:
40368.235 Da
References
  1. Wentland MP, Lou R, Lu Q, Bu Y, VanAlstine MA, Cohen DJ, Bidlack JM: Syntheses and opioid receptor binding properties of carboxamido-substituted opioids. Bioorg Med Chem Lett. 2009 Jan 1;19(1):203-8. doi: 10.1016/j.bmcl.2008.10.134. Epub 2008 Nov 7. [19027293 ]
General Function:
Protein phosphatase 2a binding
Specific Function:
NMDA receptor subtype of glutamate-gated ion channels with reduced single-channel conductance, low calcium permeability and low voltage-dependent sensitivity to magnesium. Mediated by glycine. May play a role in the development of dendritic spines. May play a role in PPP2CB-NMDAR mediated signaling mechanism (By similarity).
Gene Name:
GRIN3A
Uniprot ID:
Q8TCU5
Molecular Weight:
125464.07 Da
References
  1. Hara K, Minami K, Sata T: The effects of tramadol and its metabolite on glycine, gamma-aminobutyric acidA, and N-methyl-D-aspartate receptors expressed in Xenopus oocytes. Anesth Analg. 2005 May;100(5):1400-5, table of contents. [15845694 ]
General Function:
Opioid receptor activity
Specific Function:
G-protein coupled opioid receptor that functions as receptor for endogenous alpha-neoendorphins and dynorphins, but has low affinity for beta-endorphins. Also functions as receptor for various synthetic opioids and for the psychoactive diterpene salvinorin A. Ligand binding causes a conformation change that triggers signaling via guanine nucleotide-binding proteins (G proteins) and modulates the activity of down-stream effectors, such as adenylate cyclase. Signaling leads to the inhibition of adenylate cyclase activity. Inhibits neurotransmitter release by reducing calcium ion currents and increasing potassium ion conductance. Plays a role in the perception of pain. Plays a role in mediating reduced physical activity upon treatment with synthetic opioids. Plays a role in the regulation of salivation in response to synthetic opioids. May play a role in arousal and regulation of autonomic and neuroendocrine functions.
Gene Name:
OPRK1
Uniprot ID:
P41145
Molecular Weight:
42644.665 Da
References
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