Atropa Belladonna is a perennial herb, with a thick, branched, fleshy, creeping root, and annual, erect, round, dichotomously branched, leafy, slightly downy stems, about 3 feet high. The leaves are lateral, mostly two together, of unequal size, ovate, acute, entire, soft, of a dull-green color, smooth and borne on short petioles. The flowers are imperfectly axillary, solitary, stalked, large, drooping, dark, dull-purple in the border, paler downward. The calyx is green, 5-parted, permanent, and nearly equal. The corolla is campanulate, with a short tube, and limb divided into 5, shallow, nearly equal segments. Stamens 5; filaments nearly as long as the corolla tube; anthers cordate and 4-lobed; stigma capitate and 2-lobed. The fruit is a 2-celled, many-seeded berry, subtended by the enlarged calyx; it contains reniform seeds (L.—Smith). When bruised the whole plant exhales a fetid odor.
The main constituents of belladonna are as follows: Atropine (C17H23NO3). Hyoscyamine (C17H23NO3), sometimes the principal constituent of belladonna root. It is convertible into atropine by heat; conversion also takes place in the plant itself. Atropamine (C17H21NO2) is identical with the apoatropine obtained by Pesci, in 1882, by the action of nitric acid upon atropine (O. Hesse, 1893). It is convertible into belladonnine by the action of HCl or KOH. Belladonnine (C17H21NO2) (Hübschmann) is an amorphous alkaloid, and is obtainable from hyoscyamine or atropine by heating these alkaloids from 120° to 130° C. (248° to 266° F) for several hours. By raising the temperature gradually, transformation takes place with products resulting in the following order: Hyoscyamine, atropine, atropamine, and belladonnine. Ɣ Hyoscine (Cl7H17NO4), discovered by Ladenburg in Hyoscyamus niger, occurs in belladonna root in small amounts (Schuette, 1892). O. Hesse, in 1893, showed its identity with scopolamine, an alkaloid obtained from the root of Scopolia atropoides, B. and P. (S. carniolica, for which E. Schmidt, in 1892, had found the formula, C17H21NO4. Earlier analyses show the presence in belladonna of chrysatropic acid (Kunz), the concentrated solutions of which show green and blue fluorescence, atrosin, a red-coloring principle in the root (Hübschmann), succinic acid in the herb, malates, and oxalates, combined with sodium, potassium and magnesium salts, gum, wax, asparagin, chlorophyll (in the leaves), starch, and albuminous bodies.
Effect of Atropa belladonna on the central nervous system
The Atropa belladonna alkaloids atropine and scopolamine are known to be antagonist for muscarinic receptors. They block the muscarinic receptor acetylcholine, which plays an important role in the functioning of the brain for learning, memory and orientation. In the event of the muscarinic blockade, the absence of acetylcholine causes dysfunctional memory, disorientation and hallucination[2]. The respiratory rate increases and in some cases of overdose, leads to respiratory and cardiovascular failure.
Effect of Atropa belladonna on peripheral nervous system
The alkaloid atropine acts as muscarinic antagonist and blocks the parasympathetic postganglionic muscarinic receptors[1,2]. Atropine has a stronger effect than scopolamine in producing tachycardia and cardiovascular changes, although the peripheral effects of both atropine and scopolamine are the same. The signs of peripheral effects manifested by the parasympathetic block include decreased secretions causing dryness of mouth, flushed skin, mydriasis, vomiting, constipation, urinary retention, fever, tachycardia and hypertension[1,2].
Atropa belladonna intoxication
The severity of the symptoms caused by Atropa belladonna poisoning may vary from mild to moderate to severe, depending on the dose and source. The concentration of the alkaloids present in the berries and leaves may also differ depending on the species. Some species of Atropa belladonna are hybrid and may not produce all the symptoms of toxic anticholinergic syndrome[1]. Repetition should also be kept in mind when determining the severity of the symptoms, as central effects are dose and source dependant [1,2]. Atropine crosses the blood brain barrier and patients with central anti-cholinergic syndrome show loss of memory, confusion, disorientation, hallucination, in-coordinated movements and agitated delirium with acute psychosis [1,2]. Severe cases of central anti-cholinergic toxidrome may present with coma, seizures, respiratory and cardiovascular failure [2]. The peripheral toxicity produced by the alkaloids of Atropa belladonna causes inhibition of secretions and relaxation of smooth muscles in the gastro-intestinal and urinary tract, leading to dryness of mouth, constipation, diminished bowel sounds or ileus and urinary retention. The heart rate increases (tachycardia) with hypertension as a result of parasympathetic block caused by anti-holinergic agents. Ocular changes include pupillary dilation with paralysis of the ciliary muscle which results in loss of accommodation.
In Europe, through ancient times, plants from deadly nightshades were used to treat various airway diseases e.g. the fumes from the burnt plants were inhaled for relief from ronchoconstriction. Muscarinic antagonists are known to be used as bronchodilators in asthma treatments. Due to their side effects, the anti-cholinergic drugs are not the first line of treatment; instead β-adrenergic receptor agonists and anti-inflammatory corticosteroids are routinely administered in patients with asthma and chronic obstructive pulmonary diseases. In the late 1800s, Atropa belladonna was therapeutically used to treat Parkinson’s diseases because of its naturally occurring alkaloids, atropine and scopolamine. Atropine is also effective in treating certain cardiovascular conditions like bradycardia, though low doses of atropine have shown to cause bradycardia. Atropine is also used as a premedication in anesthesia, along-with other anticholinergics, since it decreases secretions. Atropa belladonnaalkaloids act as anti-emetics, anti-spasmodic and are also effective in the treatment of gastro-intestinal ulcers.
Keep it in isolation in a dry, well-ventilated and sheltered place. Protected from moisture. Recommended storage temperature is 18-20 ° С and humidity of air is 30-40%. Shelf life: 3 years.
