1966 年 86 巻 10 号 p. 877-882
The water-soluble fraction of the Chinese drug, "Bezoar Orientale" was deproteinized with trichloroacetic acid, the glacial acetic acid solution of its fraction was extracted with ether, and the ether extract was decolorized with animal charcoal. The ether extract was purified by ethanol and a crude peptide-like substance was obtained. The aqueous solution of this substance showed pH 5. The thin-layer chromatogram of the substance gave two Ninhydrinpositive spots which had absorption maximum at around 280 mμ. This substance showed a marked contraction of digestive smooth muscles and this activity is selectively inhibited by atropine. The substance effects transitory fall of blood pressure in rabbits and this effect is also inhibited by atropine. In other words, this substance has an acetylcholine-like pharmacological activity.