The Solanaceae include more than 2,500 species of tropical and temperate regions, many from South America (potato, tomato, peppers, tobacco) and the majority belong to the genus Solanum.
The important species in Western medicine are among the genera Datura, Atropa (deadly nightshade), Hyoscyamus (henbane).
The datura are herbs, rarely shrubs or shrubs, very poisonous. Some are decorated with flowers and foliage, many grow spontaneously in the rubble, waste places, bordering crops, roads and housing.
The datura stramonium is cosmopolitan, other species are more localized;
in India, Africa and naturalized in the Mediterranean
(Mexico and Caribbean)
in the Andean region.
The datura stramonium (officinalis) is an annual plant with dark green leaves cut, flower solitary, white, sometimes purple, large sizes (5 to 10 cm). The fruit is a spiny capsule, as often in the Datura genus, containing many small seeds.
COMPOSITION AND CHEMICAL PROPERTIES
The datura and its cousins belladonna and henbane have a similar chemical composition, 15 to 20% of minerals and especially 0.2 to 0.5% of tropane alkaloids (see glossary) of hyoscyamine and scopolamine.
All parts of Datura contain but in the leaves as the concentration is highest.
The hyoscyamine and atropine have the same chemical formula and the same pharmacological activity.
The first is optically active, the second is not (racemic) and the latter is used in medicine, although probably not present in the living plant.
They are parasympathicolytiques (see glossary) that competitively inhibit the reversible binding of acetylcholine receptors and thus provide an effect apparently sympathicomimetic:
* Fast enough tachycardia with slightly increased blood pressure,
* Decrease in bowel movements, tone of the ureters and bile but increased the pressure in the bladder, removal of bronchospasm due to acetylcholine,
* Significant reduction in secretions: saliva, sweat, bronchial, lacrimal, digestive,
* Mydriasis (pupil dilation) by progressive paralysis of the constrictor muscles of the iris.
At toxic doses, there is excitement central nervous system (CNS) with agitation, hallucinations, delirium, confusion, low dose on the contrary, a trend sedative.
Scopolamine also affects parasympathicolytique but less marked, with more cons net effects on the CNS: sedative, hypnotic, with amnesia and depressive tendency. A high dose is a disabling to coma.
The Datura is a hallucinogenic plant that has been used at all times by the "sorcerers", "Shaman" and "healing medium".
Its use is particularly dangerous because the amount of leaf smoke or ingest for the hallucinogenic effect is difficult to dose.
A high dose (equivalent to some g leaf), delirium is furious with convulsions and coma and sometimes death at low doses the effects are just parasympathicolytiques.
Hallucinations fantastic start 2 to 4 hours after eating and lasts several hours are powerful, that "the grass of the devil", the draft of witches brew or initiation (see "the grass and the little devil Smoke "by C. Castaneda).
In East Africa the datura has been used as ordeal poison in "judgments of God," the ordeal.
In India many suicides or poisoning criminals owed.
But the thorn is also a medicinal herb, the dosage forms is country:
in France found the powder datura, dyeing and soft extract of datura, there were the leaves of datura.
The datura is much less used belladonna in France, it is a component of cough syrups and entered a few years ago in the composition of cigarettes and powder asthma.
This is an important plant in homeopathy: datura 3DH sedative, antispasmodic 4DH asthma, 3CH regulator of arterial circulation, 6CH bronchial disorders.
We will not detail the particulars of tropane alkaloids extracted from Datura: atropine and scopolamine.
* Atropine: premedication, ophthalmology, events and spasmodic pain in the digestive tract and urinary tract.
* Scopolamine: premedication and parkinsonism, motion sickness (with the risk of urinary retention in cases of prostate disorders).
More anecdotally, is still used in tropical leaf datura dried fumigation to relieve the asthma attack and the green leaf slightly heated poultice on painful joints.