WHO monographs on selected medicinal plants - travolekar.ru

<strong>WHO</strong> <strong>monographs</strong> on selected medicinal plants
tion. At the time of death (day 20), blood from portal and peripheral veins,
and samples from intestinal mucosa, amnion, amniotic cells and placenta
were collected, and the tissues were cultured in the presence of ricinoleic
acid or indometacin. The concentrations of prostaglandin E2 in the media
or blood were measured by radioimmunoassay methods. The prostaglandin
E2 levels in the portal vein increased; the prostaglandin E2 levels in
peripheral blood showed no significant changes; the prostaglandin E2 levels
in the tissues of the intestinal mucosa, placenta, amnion and amniotic
cells were increased. Ricinoleic acid stimulated the synthesis of prostaglandin
E2 in the tissues in vitro (27).
Toxicology
Toxicity studies on castor oil have been performed by incorporating the
oil into feed rations at concentrations as high as 10% of the diet. Animals,
F344/N rats and B6C3F1 mice, of both sexes were fed the diet for
13 weeks. Exposure to castor oil at dietary concentrations as high as 10%
in 13-week studies did not affect survival or body weight gains of rats or
mice (10 per sex and dose). No biologically significant effects were noted
in haematological analyses in rats. Small increases in total bile acids and in
serum alkaline phosphatase were noted at various times during the studies
in rats receiving the higher dietary concentrations of castor oil. Liver
weights were increased in male rats receiving the 10% dietary concentration
and in male and female mice receiving diets containing 5% or 10%
castor oil. However, no histopathological lesions were associated with
these liver changes, nor were there any compound-related morphological
changes in any organ in rats or mice. Thus, no significant adverse effects
of castor oil administration were noted (28).
Epithelial cells, isolated from small intestine of hamsters, were used to
measure in vitro cytotoxicity of the crude drug. The cytotoxicity of ricinoleic
acid (castor oil) was assessed by:
— exclusion of trypan blue;
— release of intracellular (prelabelled) 51Cr; and
— inhibition of cellular uptake of 3-O-methylglucose.
Ricinoleate produced weak but dose-dependent (0.1–2.0 mM) cytotoxicity
as assessed by all three methods (29).
In an in vivo study, segments of rabbit ileum were examined by scanning
electron microscopy after exposure to various compounds known to
stimulate fluid secretion in the small intestine. After perfusion with ricinoleate
(castor oil) at a concentration of 10 mM, striking changes were
observed at villus tips and on the apicolateral surfaces of villi; erosions of
the tips were confirmed by light microscopy of the same pieces of tissue
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