Veratrum

Veratrum

Taxobox
name = "Veratrum"


image_width = 250px
image_caption = "Veratrum album"
regnum = Plantae
divisio = Magnoliophyta
classis = Liliopsida
ordo = Liliales
familia = Melanthiaceae
genus = "Veratrum"
genus_authority = L.
subdivision_ranks = Species
subdivision = See text.

"Veratrum" is a genus of coarse, highly poisonous perennial herbs of the Melanthiaceae family. In English they are usually known as the False hellebores. Members of "Veratrum" are known both in western herbalism and traditional Chinese medicine as toxic herbs to be used with great caution. It is one of the medicinals {"Li lu") cited in Chinese herbal texts as incompatible with many other common herbs because of its potentiating effects. Especially, many root (and root-shaped) herbs, particularly ginseng, san qi, and hai seng, will create and or exacerbate a toxic effect [Bensky, D., Clavey, S., Stoger, E. (3rd edition 2004) Materia Medica Eastland Press, Inc. Seattle, p 461] .

"Veratrum" species are used as food plants by the larvae of some Lepidoptera species including Setaceous Hebrew Character.

Birth defects in livestock grazing on "Veratrum californicum" (native to the western United States) led to the study of cyclopamine and jervine which are important in animal developmental biology including cancer treatment.

Distribution

Widely distributed in montane habitats throughout North America. Veratrum species prefer full sunlight and deep, wet soils, and are common in wet mountain meadows, swamps, and near streambanks. Veratrum species occur from Alaska south into the mountains of California, and are widely distributed throughout the Rocky Mountains. Veratrum is very abundant in Eastern North America from Quebec southward through the Appalachians into North Carolina.

Uses and toxicity

"Veratrum" species contain highly toxic steroidal alkaloids that can cause rapid cardiac failure and death if ingested or introduced into the bloodstream. Native Americans used the juice pressed from the roots of this plant to poison arrows before combat. The dried powdered root of this plant was also used as an insecticide. [Edible and Medicinal plants of the West, Gregory L. Tilford, ISBN 0-87842-359-1]

"Veratrum" species are an important source of life-saving medications used in modern medical preparations which lower blood pressure, slow the heartbeat, and are used for cancer treatment. Cyclopamine derived from "Veratrum" species is a potent teratogen that is an effective treatment for several deadly and malignant cancers, including basal cell carcinoma, medulloblastoma, rhabdomyosarcoma, glioblastoma, and multiple myeloma [cite journal|title=Effects of oncogenic mutations in Smoothened and Patched can be reversed by cyclopamine|journal=Nature|date=2000-08-31|pages=1005–9|volume=406|issue=6799|doi=10.1038/35023008|author=Beachy, Philip A.PMID|10984056] .

During the winter months, when the plant enters its dormant stage, it degrades and metabolizes most of its toxic alkaloids. Herbalists and Native Americans who used this plant for medicinal purposes harvested the roots during the winter months when the levels of toxic constituents were at their lowest. "Veratrum" species produce highly toxic steroidal alkaloids only when the plants are in active growth. The root and the seeds are the most poisonous parts of the plant.

Western American Indian tribes have a long history of the use of this plant as an effective treatment for cancerous tumors, and combined minute amounts of the winter-harvested root of this plant with "Salvia dorii" to potentiate its effects and reduce the toxicity of the herb. The plants teratogenic properties and ability to induce severe birth defects were well known to Native Americans. [Edible and Medicinal plants of the West, Gregory L. Tilford, ISBN 0-87842-359-1]

The roots of "V. nigrum" and "V. schindleri" have been used in Chinese herbalism (where plants of this genus are known as "li lu" (藜蘆). Li lu is used internally as a powerful emetic of last resort, and topically to kill external parasites, treat tinea and scabies, and stop itching. [Bensky, D., Clavey, S., Stoger, E. (3rd edition 2004) Materia Medica Eastland Press, Inc. Seattle, p 461] . Some herbalists refuse to prescribe li lu internally, citing the extreme difficulty in preparing a safe and effective dosage, and that death has occurred at a dosage of 0.6 grams [Bensky, D., Clavey, S., Stoger, E. (3rd edition 2004) Materia Medica Eastland Press, Inc. Seattle, p 461] .

elected species

*"Veratrum album"
*"Veratrum californicum"
*"Veratrum fimbriatum"
*"Veratrum insolitum"
*"Veratrum latifolium"
*"Veratrum lobelianum
*"Veratrum nigrum"
*"Veratrum parviflorum"
*"Veratrum tenuipetalum"
*"Veratrum viride"
*"Veratrum woodii"

References

External links

* [http://plants.usda.gov/java/profile?symbol=VERAT USDA Plants Profile]


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Look at other dictionaries:

  • Veratrum — Vératres …   Wikipédia en Français

  • Veratrum — Ve*ra trum, n. [L. veratrum hellebore.] (Bot.) A genus of coarse liliaceous herbs having very poisonous qualities. [1913 Webster] Note: Veratrum album of Europe, and Veratrum viride of America, are both called hellebore. They grow in wet land,… …   The Collaborative International Dictionary of English

  • Verātrum — (V. L.), Pflanzengattung aus der Familie der Melanthacea Veratreae, 23. Kl. 1. Ordn. (6. Kl. 3. Ordn.) L.; mit sechstheiliger Blüthenhülle, 6 fast kugeligen Staubbeuteln, Frucht aus 3 oben freien Kapseln bestehend, welche zweiklappig u. vielsamig …   Pierer's Universal-Lexikon

  • Verātrum — L. (Germer, Nieswurz), Gattung der Liliazeen, ausdauernde Kräuter mit dickem, walzenförmigem Wurzelstock, einfachem Stengel, meist breiten, oft gefalteten, den Stengel scheidig umfassenden Blättern, weißlichen, grünlichen oder schwarz purpurnen… …   Meyers Großes Konversations-Lexikon

  • Veratrum — Verātrum L., Pflanzengattg. der Liliazeen, hohe Kräuter mit dicken Rhizomen. V. album L. (weiße Nießwurz, Germer), Alpenpflanze, enthält in ihrem Wurzelstock das dem Veratrin (s.d.) ähnliche Jervin, weshalb dieser zu Schnupfpulver benutzt wird. V …   Kleines Konversations-Lexikon

  • Veratrum — Género de hierbas venenosas de la familia de los lirios. Los rizomas desecados de eléboros británicos y norteamericanos proporcionan alcaloides utilizados como agentes antihipertensivos. Diccionario Mosby Medicina, Enfermería y Ciencias de la… …   Diccionario médico

  • veratrum — [və rā′trəm] n. 〚L: see VERATRINE〛 1. HELLEBORE (sense 2) 2. the dried rhizomes of certain hellebores, once used in medicine * * * ▪ plant genus       genus of poiso …   Universalium

  • Veratrum —   [v ; lateinisch], die Pflanzengattung Germer.   …   Universal-Lexikon

  • veratrum — [və rā′trəm] n. [L: see VERATRINE] 1. HELLEBORE (sense 2) 2. the dried rhizomes of certain hellebores, once used in medicine …   English World dictionary

  • Veratrum — Germer Weißer Germer (Veratrum album) Systematik Abteilung: Bedecktsamer (Magnoliophyta) …   Deutsch Wikipedia

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