Peyote (Lophophora williamsii)
CACTACEAE, Cactus Family
The most notorious hallucinogenic dicotyledon of North America is peyote, Lophophora williamsii, a spineless cactus that grows in the Chihuahuan Desert. The cone- to carrot-shaped plant grows buried in the desert soil, so that only the rounded, upper gray-green surface can be seen, and below-ground the stem is yellowish-white. Typically peyote cactus occurs in small clusters of stems (no leaves), each with a taproot, and small stems (clones) bud off the thicker and older mother plant. Rarely this plant is found, because it has such a cryptic nature, most commonly safely hidden beneath the canopy of a desert shrub.
The individual stem is traditionally called a "button." The photosynthetic top of a button is sliced horizontally and eaten fresh, leaving behind the bottom portion that has a core of very strange wood, described a quarter of a century ago by Prof Gibson. Sometimes the white hairs arising from the areoles of this cactus are removed. The mucilaginous stem is chewed, and within a half hour vomiting is commonly experienced. Stem parenchyma cells contain alkaloids--potentially more than four dozen and derivatives--of which mescaline, 3,4,5-trimethoxy-beta-phenylethamine, is the primary hallucinogen. Its chemical structure makes it one of the simplest alkaloids, very similar to the neurotransmittor epinephrine. Several other cacti also manufacture mescaline, most notably Trichocereus pachanoi, which is an hallucinogen from Peru, and likely mescaline occurs in many cacti but at concentrations so low that hallucinations could not be produced even if you ate a truck load of the stems. Mescaline has been fairly uncomplicated to synthesize in the laboratory, a feat performed during the 1960's drug culture, especially for the colorful, occasionally terrifying, sensual experience.
In the plant, the principal precursor of mescaline is tyrosine, which is made from phenylalanine. Tyrosine and phenylalanine are two of the typical 20 amino acids of organisms, whereas, if memory serves, the laboratory synthesis of mescaline involved phenol as a precursor. Synthetic and natural mescaline apparently act at the base of the brain in serotonin-sensitive neurojunctions, which then triggers cascading effects on synapses of the senses.
Peyote, as peyotl zacatacensi, was mentioned in key publications of 16th and 17th century post-Conquest Mexico, being used by native tribes, but the Catholic Church fought against its use. Much tribal use was by the Tarahumara of western Chihuahua and Huichol of western Zacatecas and neighboring Nayarit, where peyote use became a major portion of native religions, collectively termed peyotism. Peyotism has more recently become a sacrament of the Native American Church within the United States.