Saegusa Yoshiki, Sugiyama Atsushi, Takahara Akira, Nagasawa Yoshinobu, Hashimoto Keitaro
Department of Pharmacology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Yamanashi, Japan.
J Pharmacol Sci. 2003 Sep;93(1):62-8. doi: 10.1254/jphs.93.62.
Given a lack of information, we assessed the effects of Kampo medicines: Dai-saiko-to, Tsu-do-san, San'o-shashin-to, and Sairei-to, which have been used for various gastrointestinal diseases, on the phosphodiesterase activity and smooth muscle tone of the gastrointestinal tract. Clinically relevant concentrations of each Kampo extract (0.1 - 1 mg/ml) decreased the phosphodiesterase activity as well as smooth muscle tone. The extent of phosphodiesterase inhibition as well as smooth muscle relaxation by these Kampo extracts was prominent for the lower gastrointestinal tract. Also, there was a good correlation between the extents of drug-induced phosphodiesterase inhibition and smooth muscle relaxation, indicating the presence of their causal link. These results may partially provide the basis for understanding the mechanism of the clinical utility of Kampo extracts in gastrointestinal tract diseases.
