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A Non-Selective Antagonist of Endothelin Receptors

Cat #: SPE-320
Lyophilized Powder yes
  • Bioassay Tested
  • Origin Synthetic
    MW: 927 Da
    Purity: ≥98% (HPLC)
    Effective concentration 0.5 – 1 µM.
    Sequence DDDXLW.
    Modifications X = D-(2-thienyl)glycine, Tryptophan and aspartic acid-4 are in the D-isomer.
    Aspartic acid-2 is modified with the group α-amino-γ-oxo-4-phenyl-1-piperazinebutanoyl.
    Chemical name 2-[(2R,5S,8S,11S,14S,17R)-8-(carboxymethyl)-17-(1H-indol-3-ylmethyl)-14-(2-methylpropyl)-3,6,9,12,15,18-hexaoxo-5-[2-oxo-2-(4-phenylpiperidin-1-yl)ethyl]-11-thiophen-2-yl-1,4,7,10,13,16-hexazacyclooctadec-2-yl]acetic acid
    Molecular formula C45H51N9O11S.
    CAS No.: 157380-72-8
    Activity TAK-044 is a non-selective endothelin receptor antagonist1.
    1. Watanabe. T. et al. (1995) Br. J. Pharmacol. 114, 949.
    Shipping and storage Shipped at room temperature. Product as supplied can be stored intact at room temperature for several weeks. For longer periods, it should be stored at -20°C.
    Solubility Soluble in DMSO. Centrifuge all product preparations before use (10000 x g 5 min).
    Storage of solutions Up to four weeks at 4°C or three months at -20°C.
    Our bioassay
    • Alomone Labs TAK-044 inhibits Endothelin-B receptor-mediated Ca2+ mobilization in CHO cells.
      Alomone Labs TAK-044 inhibits Endothelin-B receptor-mediated Ca2+ mobilization in CHO cells.
      Cells were loaded with Calcium-6 dye, incubated with different concentrations of TAK-044 (#SPE-320), and stimulated by 30 nM Endothelin-1 (EC80). Changes in intracellular Ca2+ were monitored as changes in relative fluorescence (RLU) using FLIPRTETRA.  IC50 was determined as 0.66 µM.
    References - Scientific background
    1. Watanabe. T. et al. (1995) Br. J. Pharmacol. 114, 949.
    2. Saeki, T. et al. (1991) Biochem. Biophys. Res. Commun. 179, 286.
    3. Xie, C. and Wang, D.H. (2009) Hypertension 54, 1298.
    Scientific background

    TAK-044 is a synthetic peptide that acts as a non-selective ET-B (endothelin B) and ET-A (endothelin A) receptor antagonist, receptors that belong to the G-protein coupled receptor (GPCR) superfamily. In a study conducted on rats the compound showed high inhibitory effects on the extension of myocardial infarct size after coronary artery occlusion-reperfusion1. TAK-044 inhibits radiolabelled ET-1 binding from the rabbit ventricular and cerebellar preparation with an IC50 value of 3.8 nM and 130 nM, respectively1.

    Endothelin receptors include two subtypes: ET-A and ET-B. ET-A receptors are predominantly detected in peripheral tissues, especially in vascular smooth muscle tissues to mediate vasoconstriction. They are also present in several regions of the brain. ET-B receptors play an important role in regulating renal function and blood pressure and are expressed in sensory nerves. They are mainly present in medium- and large-sized cell bodies of human trigeminal ganglia2,3.

    Target Endothelin receptors
    Peptide Content: 100%
    Last update: 06/11/2022

    TAK-044 (#SPE-320) is a highly pure, synthetic, and biologically active cyclic peptide.

    For research purposes only, not for human use
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