1968 年 18 巻 1 号 p. 19-29
The retarding effect of the orally administered acidic protease (TE-P), isolated from Trametes sanguinea, on the spontaneous delivery in the pregnant rats but not in the pregnant rabbits has been reported by Shimamoto (1). Though exact nature of the retarding mechanism is still unknown, the enzyme is assumed to be absorbed from the gastrointestinal tract without loosing the proteolytic activity and to exert the interfering with the delivery process in virtue of some pharmacological effects of the proteolytic products of the tissue or plasma. This indication was further supported by the evidence that the in vitro incubation of the commercial globulin with the adequate concentrations of TE-P at the acidic reaction produced the pharmacologically active substance unique in evoking a slow contraction of the smooth muscle (2). The present authors have also confirmed that the similar incubation of the homogenates of the rat spleen, kidney and liver with the enzyme resulted in the formation of the active substance, which definitely differs pharmacologically from acetylcholine, histamine, 5-hydroxytryptamine and bradykinin. Moreover, it has been confirmed that the incubation of the tissue homogenates alone at the acidic reaction produces another active substance, which contracts the isolated rat uterus, retarded in onset and slow in progress. In the present experiments, efforts were made to separate pharmacologically and biochemically both active substances in order to know the pharmacological properties of the proteolytic substance in the incubation of the liver homogenates with TE-P.