Ibotenic acid is an isoxazole originally isolated from Amanita mushrooms. The toxic fungi Amanita muscaria, commonly known as the fly agaric, was used to prepare the soma. The feelings of euphoria or invincibility experienced by those who drank it were eventually attributed to a group of isoxazoles centuries later. Two of these - ibotenic acid and muscimol - were first isolated from the Japanese mushroom Amanita ibotengutake in the 1960s, but found in abundance in all Amanita mushrooms. Ibotenic acid is a non-protein amino acid that is unstable and easily decarboxylated to muscimol. Ibotenic acid is a glutamate agonist, acting at glutamate receptors. Ibotenic acid is neurotoxic and used to induce cerebral lesioning in animal models.