Catalog Number: 1310
Chemical Name: 6,12,19,20,25,26-Hexahydro-5,27:13,18:21,24-trietheno-11,7-metheno-7H-dibenzo [b,n] [1,5,12,16]tetraazacyclotricosine-5,13-diium dibromide
Biological Activity
Highly potent, non-peptidic blocker of the apamin-sensitive Ca2+-activated K+ channel (KCa2.1) (IC50 = 3 nM in rat sympathetic neurons). Blocks hKCa2.1 and rKCa2.2 channels expressed in HEK 293 cells with IC50 values of 762 and 364 pM respectively.
Technical Data
  • M.Wt:
  • Formula:
  • Solubility:
    Soluble to 10 mM in DMSO
  • Purity:
  • Storage:
    Desiccate at RT
  • CAS No:
The technical data provided above is for guidance only. For batch specific data refer to the Certificate of Analysis. All Tocris products are intended for laboratory research use only.
Additional Information
Licensing Caveats:
Sold with the permission of University College, London
Background References
  1. Synthesis, molecular modeling, and pharmacological testing of bis-quinolinium cyclophanes: potent, non-peptidic blockers of the apamin-sensitive Ca2+-activated K+ channel.
    Campos Rosa et al.
    J.Med.Chem., 2000;43:420
  2. Compounds that block intermediate-conductance (IKCa) and small-conductance (SKCa) calcium-activated potassium channels.
    Malik-Hall et al.
    Br.J.Pharmacol., 2000;129:1431
  3. Pharmacological characterization of small-conductance Ca2+-activated K+ channels stably expressed in HEK 293 cells.
    Strobaek et al.
    Br.J.Pharmacol., 2000;129:991

The citations listed below are publications that use Tocris products. Selected citations for UCL 1684 include:

Showing Results 1 - 10 of 11

  1. Knockdown of the small conductance Ca(2+) -activated K(+) channels is potently cytotoxic in breast cancer cell lines.
    Authors: Abdulkareem Et al.
    Heart Rhythm
  2. 5-hydroxytryptamine has an endothelium-derived hyperpolarizing factor-like effect on coronary flow in isolated rat hearts.
    Authors: Chien and Su
    J Biol Chem
  3. Platelet-derived growth factor receptor-α-positive cells and not smooth muscle cells mediate purinergic hyperpolarization in murine colonic muscles.
    Authors: Kurahashi Et al.
    Am J Physiol Cell Physiol
  4. Synaptic NMDA receptor-dependent Ca2+ entry drives membrane potential and Ca2+ oscillations in spinal ventral horn neurons.
    Authors: Alpert and Alford
    PLoS One
  5. Proarrhythmic effect of blocking the small conductance calcium activated potassium channel in isolated canine left atrium.
    Authors: Hsueh Et al.
    J Biomed Sci
  6. Iberiotoxin-sensitive and -insensitive BK currents in Purkinje neuron somata.
    Authors: Benton Et al.
    J Neurophysiol
  7. Dynamic interplay of excitatory and inhibitory coupling modes of neuronal L-type calcium channels.
    Authors: Geier Et al.
    Am J Physiol Cell Physiol
  8. Twenty-four-hour exposure to altered blood flow modifies endothelial Ca2+-activated K+ channels in rat mesenteric arteries.
    Authors: Hilgers Et al.
    J Pharmacol Exp Ther
  9. Allosteric block of KCa2 channels by apamin.
    Authors: Lamy Et al.
    PLoS One
  10. Upregulation of intermediate calcium-activated potassium channels counterbalance the impaired endothelium-dependent vasodilation in stroke-prone spontaneously hypertensive rats.
    Authors: Giachini Et al.
    Transl Res
  11. Glucose stimulates Ca2+ influx and insulin secretion in 2-week-old β-cells lacking ATP-sensitive K+ channels.
    Authors: Szollosi Et al.
    Br J Pharmacol
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