Rauwolfia Serpentina in Essential Hypertension

jHauwolfia serpentina has been known as a medicinal plant in India for a long time but its use in the treatment of hypertension is of comparatively recent origin. The dried root contains 1 per cent of total alkaloids besides resin, starch, potassium carbonate, phosphate, silicate and traces of iron and manganese (Sen and Bose, 1931). Siddiqui and Siddiqui (1931) found two groups of alkaloids and phytosterol, oleic acid and unsaturated alcohols. The alkaloids were named (a) Ajmaline group : (i) Ajmaline, (ii) Ajmalinine, (Hi) Ajmalicine, and (b) Serpentine group: (i) Serpentine, (ii) Serpentinine. Working on frogs they found that the ajmaline group acts as a general depressant to heart, respiration and nerves, whereas serpentine group paralyses respiration, depresses nerves but stimulates the heart. Sen and Bose (1931) demonstrated that the alkaloids separated by them caused slight fall of blood pressure and stimulation of respiration in the cat. Chopra et al. (1933) also noted a respiratory and cerebral depressant effect but the systemic blood pressure was lowered due to splanchnic vasodilatation. Roy (1931) showed that large doses produced sleep with diminution of reflexes and sensation of pain. The sedative property probably accounts for its use in cases of insanity. Twenty to thirty grains of the powdered root have been administered by Sen and Bose (1931) with both sedative effect and reduction of blood pressure. The sedative and hypnotic property of the root was found to be present in the alcoholic extract, in the total alkaloids and the total alkaloids free from ajmaline, serpentine and serpentinine. The three alkaloids are medullary stimulants whereas the sedative principle is a medullary depressant (Chopra et al, 1943). Gupta et al. (1944) have later shown that a petroleum-insoluble, alcohol-soluble resin fraction produces hypnosis and sedation without any fall of blood pressure. Bhatia and Kapur (1944) studied the effects of neo-ajmaline and isoajmaline obtained by Siddiqui from Dehra Dun variety of plant roots. They found that both the alkaloids lowered blood pressure in the intact spinal and decerebrate animals (cats and dogs) in normal condition and in experimental hypertension produced by adrenaline or ephedrine. Raymond Harriet (Henry, 1949) observed that ajmalinine provoked hypotension with renal vasodilatation and exerted a true sympatheticolytic action. Ajmaline and serpentine were also found to be hypotensive (Henry, 1949). Vakil (1949) obtained a lowering of systolic and diastolic blood pressure in 50 patients after 4 weeks' treatment (Serpina, 1 tablet t.d.s. X 4 weeks) in 74 and 72 per cent respectively and the hypotensive action was evident 4 weeks after stoppage of treatment in 74 per cent. A second course was found to be equally effective. He noticed drowsiness, lassitude, diarrhoea, anorexia, nausea and vomiting as side-effects in