ABSTRACT
Introduction Since kampo-hozais (traditional Chinese medicines) are composed of several crude drugs, for example, there are seven medicinal herbs such as Bupleuri Radix, Pinelliae Tuber, Zingiberis Rhizoma, Scutellariae Radix, Zizyphi Fructus, Ginseng Radix and Glycyrrhizae Radix in Sho-saiko-to, there are numerous ingredients in the decoction. In order to clarify the mechanism of their diverse pharmacological actions on the molecular basis, we first need to know the real active principles in our body. Most kampo-hozais such as Sho-saiko-to are administered orally as a decoction. As a result of oral administration, components, which are involved in kampo-hozais are exposed to gastric juice, other digestive enzymes and intestinal microflora in the gut. Some of their chemical structures should be transformed before the absorption into the blood. The metabolites are absorbed from the alimentary tract via the portal vein and then metabolized or detoxicated in the liver. Some of these are excreted into intestine via the bile duct, passed into enterohepatic circulation and again meet intestinal bacteria.
