Catalog Number: 0772
Chemical Name: 2-(4-Carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, potassium salt
Biological Activity
A stable, water-soluble free radical that reacts stoichiometrically with NO. Almost twice as strong an inhibitor as N(ω)-nitroarginine or N-methylarginine.
Technical Data
  • M.Wt:
  • Formula:
  • Solubility:
    Soluble to 25 mM in ethanol and to 10 mM in water
  • Storage:
    Desiccate at -20°C
  • 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.
Background References
  1. Antagonistic action of imidazolineoxy N-oxides against endothelium-derived relaxing factor/NO through a radical reaction.
    Akaike et al.
    Biochemistry, 1993;32:827
  2. Vasodilator effect of carboxy-2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl in the coronary circulation: in vivo and in vitro studies.
    Tsunoda et al.
    Eur.J.Pharmacol., 1994;262:55
  3. Discrimination by the NO-trapping agent, carboxy-PTIO, between NO and the nitrergic transmitter but not between NO and EDRF.
    Rand and Li
    Br.J.Pharmacol., 1995;116:1906

The citations listed below are publications that use Tocris products. Selected citations for Carboxy-PTIO, potassium salt include:

8 Citations: Showing 1 - 8
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  1. Selective activation of microglia facilitates synaptic strength.
    Authors: Clark Et al.
    Cardiovasc Res 2015;35:4552
  2. Endotoxin induces fibrosis in vascular endothelial cells through a mechanism dependent on transient receptor protein melastatin 7 activity.
    Authors: Echeverría Et al.
    PLoS One 2014;9:e94146
  3. Activation of the cGMP/Protein Kinase G Pathway by Nitric Oxide Can Decrease TRPV1 Activity in Cultured Rat Dorsal Root Ganglion Neurons.
    Authors: Jin Et al.
    Korean J Physiol Pharmacol 2012;16:211
  4. The role of vascular myoglobin in nitrite-mediated blood vessel relaxation.
    Authors: Ormerod Et al.
    Br J Pharmacol 2011;89:560
  5. The acute antinociceptive effect of HBO2 is mediated by a NO-cyclic GMP-PKG-KATP channel pathway in mice.
    Authors: Quock Et al.
    Brain Res 2011;1368:102
  6. Synaptic plasticity and NO-cGMP-PKG signaling regulate pre- and postsynaptic alterations at rat lateral amygdala synapses following fear conditioning.
    Authors: Ota Et al.
    PLoS One 2010;5:e11236
  7. The NO-cGMP-PKG signaling pathway coordinately regulates ERK and ERK-driven gene expression at pre- and postsynaptic sites following LTP-inducing stimulation of thalamo-amygdala synapses.
    Authors: Ping and Schafe
    Neural Plast 2010;2010:540940
  8. Synaptic plasticity and NO-cGMP-PKG signaling coordinately regulate ERK-driven gene expression in the lateral amygdala and in the auditory thalamus following Pavlovian fear conditioning.
    Authors: Ota Et al.
    Learn Mem 2010;17:221

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