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It is an evergreen, perennial, glabrous and errect undershrub
grows up to a height of 60 cm (rarely more than it). Roots are
tuberous with pale brown cork. Leaves are in whorls of three,
elliptic to lanceolate or obovate, bright green above, pale
green below, tip acute or acuminate, base tapering and slender.
Petioles long. Flowers are in many flowered irregular corymbose
cymes. Peduncles long but pedicels stout. Flowers white, often
has violet coloured tinge. Calyx glabrous, bright red and
lanceolate. Corolla is longer than calyx, tube slender, swollen
a little above the middle, lobes 3, and elliptic-oblong. Disc is
cup shaped. Drupes are slightly connate, obliquely ovoid and
purplish black in colour.
Principal Constituents:
Reserpine is the most important alkaloid present in root, stem
and leaves of the plant. It varies from 1.7 to 3.0 %. The root
barks has more than 90% of the total alkaloids in roots. The %
of the alkaloid depends on the geographical place from where the
plant is collected and also the season of collection. Generally
samples from Assam have a higher % of alkaloids (2.57 %) than
the other parts of India and December is the best month for the
collection for getting more % of alkaloids. But, age of the
plant has no effect on the % of alkaloid content (up to 4
years). Ajmalicine, ajmaline, isoajmaline, ajmalinine, chandrine,
rauwolfinine, renoxidine, rescin-namine, reserpiline, reserpin,
reserpinine, sarpagine, serpentine, serpentinine,
tetraphyllicine, yohimbine, 3-epi-a-yohimbine are the minor
alkaloids identified from samples collected from India
Pharmacology:
Reserpine has a highly complex pattern of activity. Besides the
amine concentration in brain, it is also reported to influence
the concentration of glycogen, acetyl choline, g-amino butyric
acid, nucleic acids and anti-diuretic hormone. The effects of
reserpine include respiratory inhibition, stimulation of
peristalsis, myosis, relaxation of nictating membranes, and
influence on the temperature regulating centre. It increases the
volume and free acidity of gastric secretion. Reserpine reduces
glycaemia in some cases but the effect is short-lived. In some
patients it has a stimulating effect on prothrombin activity.
Reserpine also favors permeation of blood into areas rendered
ischemic by burns1. It produces sedation and a
lowering of blood pressure. If administered orally, in
hypertension, the effects of reserpine are slow, seldom
appearing before 3-6 days of administration and continuing for
some time after withdrawal of the drug and have a cumulative
effect. It is most valuable in young patients with mild labile
hypertension associated with tachycardia. In long established
hypertension, it is best used in conjunction with more potent
hypertensive drugs such as hexamethonium or hydralazine.
Combined with polythiazide, it is a useful hypotensive in mild
to moderate thiazide, it is a useful hypotensive in mild to
moderate conditions. The response to reserpine varies in
patients and the dosage must be adjusted to individual
requirements. In severe hypertension, it may be given by
intravenous or intramuscular injection when the effect begins
within a few hours. Parenteral therapy of reserpine is indicated
in the treatment of hypertension only when oral administration
is impracticable.
Deserpidine is almost as active as
reserpine in its hypotensive and sedative activity. reduces
hypotension and inhibits intestinal movements. Given with an
equal amount of reserpine it was more hypotensive than either of
the drugs in equivalent doses. It possesses anti-fibrillar
activity. Serpentina causes marked inhibition of succinate
dehydrogenase in brain and liver tissues. It produces a systemic
and pulmonary hypotension due to a decrease in cardiac output;
there is no change in coronary flow, but coronary vascular
resistance is decreased and myocardial oxygen consumption is
unaffected. Ajmaline has been reported to stimulate respirartion
and intestinal movements. The action of ajmaline on systemic and
pulmonary blood pressure is similar to that of serpentine
Rauwolfinine has hypertensive properties on the autolysis of rat
brain and liver tissue, but to a lesser extent than reserpine.
In contrast to reserpine, the total extract of R. serpentina
inhibited the acetylcholine-induced contraction of the enervated
dorsal leech muscle. The whole crude drug is reported to contain
some principles which bring about undesirable side effects such
as purgation and sexual debility.
Medicinal Uses:
This plant is used medicinally both in the Modern Western
Medical system and also in Ayurveda, unani and folk medicine. It
helps to reduce blood pressure, depresses activity of central
nervous system and acts as a hypnotic. Snakeroot depletes
catecholamines and serotonin from nerves in central nervous
system. Refined snakeroot has been used extensively in recent
years to treat hypertension. It is used as an antidote to the
bites of poisonous reptile like snakes.
It is also used to treat dysentery and other painful affections
of the intestinal canal.
Disclaimer:
The authenticity of the above
information are not verified and established by us. You are
requested to get it verified. The above given information are
collected from various sources may be used for academic purpose.
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