ACTION OF RHODEXIN ON ISOLATED FROG'S HEART

Abstract

Omoto, or Rhodea japonica, is a plant of the family Liliaceae sometimes growing wild, but more widely cultivated as garden plant, in Japan. It has been used from olden times to prepare drugs against heart diseases but there have been rather few reports on its active principles. As shown in Table 1, Murashirna (1) has extracted rhodein from its rhizomes, Nakaya and Tanno (2) rhodeatoxin from its leaves and Kono rhodealin A also from its leaves.Recently, Nawa (3) has obtained crystalline glycosides rhodexins A and B from dried leaves and roots of Omoto by means of specially contrived methods.The chemical structure of rhodexins A and B has been ascertained to be as shown in Table 2 by Nawa et al., but only a few results of animal experiments with the glycosides have been reported to date (Table 3).The author of this paper has undertaken to test the effects of these glycosides on isolated hearts of frogs, in comparison with those of digitoxin, and thus obtain a glimpse of the action of these chemicals upon living organisms.