|Jmol-3D images||Image 1|
|Molar mass||158.11 g/mol|
|Melting point||151-152° (anhydrous); 144-146° (monohydrate)|
|Solubility in Methanol||Soluble|
|Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)|
|(what is: / ?)|
Ibotenic acid, also referred to as ibotenate, is a chemical compound and psychoactive drug which occurs naturally in Amanita muscaria and related species of mushrooms. It is a conformationally-restricted analogue of the neurotransmitter glutamate, and due to its structural similarity to this neurotransmitter, acts as a non-selective glutamate receptor agonist. Because of this, ibotenic acid is a powerful neurotoxin, and is employed as a "brain-lesioning agent" in scientific research.
Ibotenic acid acts as a potent agonist of the NMDA and group I (mGluR1 and mGluR5) and II (mGluR2 and mGluR3) metabotropic glutamate receptors. It is inactive at group III mGluRs. Ibotenic acid also acts as a weak agonist of the AMPA and kainate receptors. In addition, due to in vivo decarboxylation into muscimol, it acts indirectly as a potent GABAA and GABAA-ρ receptor agonist.
Unlike muscimol, the principal psychoactive constituent of Amanita muscaria that is understood to cause sedation and dissociation, ibotenic acid's psychoactive effects are not known independent of it serving as a prodrug to muscimol.
Use in research
Ibotenic acid is used as a brain-lesioning agent in the research environment. When injected intracranially, ibotenic acid causes the development of excitotoxic lesions of the brain. This method of experimental brain lesioning may be preferable in certain circumstances because, while it destroys neuron bodies in a particular area, tracts that cross through the target nucleus are not damaged.
"Ibotenic" comes from the Japanese name for the Amanita strobiliformis mushroom, iboten(gutake), from which it was first isolated.
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- Chilton 1975; Ott 1976a
- Erowid Psychoactive Amanitas Vault : Pharmacology of Amanita Muscaria