cicuta_virosa

Cicuta virosa L. - Apiaceae - water hemlock, Wasserschierling

Very poisonous perennial herb, 0.60-1.20m tall, native to the northern hemisphere; leaves bi- or tripinnate; flowers small, white, umbellules 15-35 flowered.

„Cicutoxin is the most poisonous and most important component of polyynes of water hemlock (Cicuta virosa). It is found in all plant parts (highest content: rhizome up to 0.2%). Related compounds in water hemlock are isocicutoxin (Z-isomer of cicutoxin), with about 25%, and virol A and B, each with about 3% share of the total polyyne content.“ http://de.wikipedia.org/wiki/Cicutoxin

„The effect of cicutoxin, the poisonous principle of the genus Cicuta, on K+currents of activated T lymphocytes was investigated using the patch clamp technique. Cicutoxin produced a dose-dependent [5 × 10− 6–7 × 10−5mol/l] and completely reversible block of K+currents with an EC50 of 1.8 × 10−5mol/l. A maximum block of 71% was achieved with cicutoxin at a concentration of 7 × 10−5mol/l. Since previous studies have shown that T lymphocyte proliferation is associated with K+currents, the effect of cicutoxin on T lymphocyte proliferation was studied by means of 3H-thymidine uptake assays. At noncytotoxic concentrations [10−7−5 × 10−5mol/l] cicutoxin reduced the3H-thymidine incorporation dose-dependently. In conclusion, cicutoxin is a potent K+current blocker which inhibits K+channel-dependent proliferation of naive and memory T lymphocytes.“
[Cicutoxin from Cicuta virosa —A New and Potent Potassium Channel Blocker in T Lymphocytes., Strauß, U., Wittstock, U., Schubert, R., Teuscher, E., Jung, S., Mix, E., Biochemical and biophysical research communications, Vol.219(2), 1996, 332-336]

„The principal toxins, cicutoxin and oenanthotoxin, belong to a group of C17 conjugated polyacetylenes. They act as (noncompetitive) gamma-aminobutyric acid antagonists in the central nervous system (CNS), resulting in unabated neuronal depolarization that can lead to seizures. Ingestion of even a small amount of plant matter may result in severe intoxication… After ingestion, the patient is most likely to experience CNS stimulatory effects including seizures that, in the absence of aggressive supportive care, can result in death. Other features include nausea, vomiting, diarrhea, tachycardia, mydriasis, rhabdomyolysis, renal failure, coma, respiratory impairment, and cardiac dysrhythmias… Treatment consists mainly of prompt airway management and seizure control, plus decontamination if achieved early and after stabilization. In the event of renal failure, the use of hemodialysis has been employed successfully.“
[Poisoning due to water hemlock., Schep, L.J., Slaughter, R.J., Becket, G., Beasley, D.M.G., Clinical toxicology, Vol.47(4), 2009, 270-278]

Cicuta virosa L.; Köhler, F.E., Medizinal Pflanzen, vol.3 t.21 (1890)