Free shipping starts now, no minimum, no coupons required!



A Modulator of 5-HT3 Receptors

Cat #: H-115
Alternative Name 5-Indolol
Lyophilized Powder yes
  • Bioassay Tested
  • Source Synthetic
    MW: 133.15
    Purity: >97%
    Effective concentration 100 µM – 1 mM.
    Chemical name 1H-indol-5-ol.
    Molecular formula C8H7NO.
    CAS No.: 1953-54-4
    PubChem CID 16054
    Activity 5-Hydroxyindole is a 5-HT3 receptor allosteric modulator which slows the desensitization of the channel1.
    1. Kooyman, A.R. et al. (1993) Br. J. Pharmacol. 108, 287.
    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 100 mM 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 5-Hydroxyindole modulates 5-HT3A receptors expressed in HEK 293T cells. 
      Alomone Labs 5-Hydroxyindole modulates 5-HT3A receptors expressed in HEK 293T cells. 
      5-HT3A receptor currents were elicited by 1µM 5-HT delivered every 3 minutes. 5-Hydroxyindole (#H-115) was applied 30 seconds before stimulation at 0.3 mM, as indicated, and inhibited the 5-HT induced peak current but increased the duration of the current response to 5-HT.
    References - Scientific background
    1. Hannon, J and Hoyer, D. (2008) Behav. Brain Res. 195, 198.
    2. Kooyman, A.R. et al. (1993) Br. J. Pharmacol. 108, 287.
    Scientific background

    Serotonin (5-hydroxytryptamine, 5-HT) is a monoamine neurotransmitter synthesized from the amino acid tryptophan by the enzyme tryptophan-decarboxylase. 5-HT3 receptor is a ligand-gated ion channel receptor of the cys-loop channel family. It is a pentamer with five subunits surrounding a central pore1.

    5-Hydroxyindole (5-indolol) is a synthetic, allosteric modulator of 5-HT3 channels. It has an effective concentration of 100 μM – 1 mM for 5-HT3A. 5-Hydroxyindole was tested in N1E-115 (neuroblastoma cells) and does not seem to elicit 5-HT receptor mediated currents on its own. However, in the presence of 5-hydroxyindole the effect of 5-HT in the same cells was significantly altered. Peak current amplitude was increased and desensitization of the 5-HT3 receptor was slowed down compared to cells solely infused with 5-HT. The effects of 5-hydroxyindole take place rapidly and are quickly reversed on washing with an external solution. Similar results can be achieved when infusing cells with other 5-HT receptor agonists. 5-Hydroxyindole enhances the peak amplitude of inward currents induced by infusion with the various 5-HT3 receptor agonists by 30-94% and slows down desensitization 2.5 – 5 fold. 5-Hydroxyindole can be used as a tool to selectively modify the desensitization of the 5-HT3 receptor2.

    Target 5-HT3 receptors
    Last update: 06/11/2022

    5-Hydroxyindole (#H-115) is a highly pure, synthetic, and biologically active compound.

    For research purposes only, not for human use
    Shipping and Ordering information