WHO monographs on selected medicinal plants - travolekar.ru

Oleum Ricini
examined by scanning electron microscopy. The changes that appeared
after treatment with ricinoleate were partially reversed during perfusion
with control buffer for 2 hours (30).
Clinical pharmacology
Laxative effect
Castor oil is an anionic surfactant laxative. Its mechanism of action is primarily
as a stool-wetting and stool-softening agent that allows the mixing
of water, lipids and other faecal material by altering intestinal permeability
and increasing net water and electrolyte secretions. The triglyceride of
ricinoleic acid in castor oil is hydrolysed within the small intestine by
pancreatic lipases to ricinoleic acid and glycerol. Ricinoleate acts as a local
irritant that increases production of cyclic adenosine monophosphate resulting
in extensive electrolyte secretion in the small intestine by reducing
net absorption of fluid and electrolytes, which ultimately stimulates intestinal
peristalsis. Because ricinoleate acts in the small intestine, accumulation
of fluid and evacuation takes place rapidly within 1–6 hours, and it
continues until the compound is excreted via the colon. Colonic emptying
is so complete that several days may elapse before a normal bowel
movement occurs (21).
To examine the effects of oleic acid and ricinoleic acid on jejunal absorption,
steady-state jejunal perfusions were done in healthy volunteers.
Taurocholate, used to solubilize the fatty acids, did not influence absorption.
Both fatty acids, at a concentration of 10 mM, reversed electrolyte
and water net movement and induced reversible fluid secretion. Ricinoleic
acid (the active principle of castor oil) was the more potent compound.
However, ricinoleic acid was absorbed more slowly than oleic acid, and
was associated with higher intraluminal concentrations (31).
A retrospective study was performed in patients who underwent elective
surgery for colorectal carcinomas. The patients were divided into
two groups according to the method of colonic cleansing that was used.
Group 1 (n = 154) used the traditional bowel preparation which included
30.0 ml castor oil given orally on the day before the operation, in addition
to three soap enemas. Patients in group 2 (n = 36) were given 500 ml
10% mannitol on the day before the operation. Infections due to wounds
developed in 26 patients from group 1 versus 13 patients from group 2.
The difference was statistically significant (16.9% versus 36.1%, p < 0.01).
The differences in the incidence of anastomotic leaks and mortality rate
between the two groups were not statistically significant. Castor-oil
treatment reduced the number of postoperative infectious wound complications
(32).
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