[Pharmacological studies of cinobufagin, in comparison with digitoxin]

General pharmacological properties of cinobufagin (CB), isolated from Senso, were compared with those of digitoxin (DT). Decrement of spontaneous movement, inhibition of writhing, prolongation of hexobarbital-induced hypnosis, muscle relaxation, inhibition of acetic acid-induced capillary permeability, hypothermia, antipyretic effect in mice; excitation of respiration in rabbits; nerve blocking action in the isolated sciatic nerve of frogs; cardiotonic effect in the isolated atria of guinea pigs; contraction of the isolated ileum of rabbits and guinea pigs; contraction of the aorta of guinea pigs; and relaxation of the isolated trachea of guinea pigs were common properties observed after separate application of CB and DT. Membrane stabilizing effect in erythrocytes of rats and inhibition of propulsive motility of the small intestine in mice were observed only after the application of CB. Inhibition of gastric juice secretion, antiinflammation on carrageenin- or dextran-induced edema, diuresis in rats, mydriasis in mice and potentiation of transmission in the neuromuscular junction of rats were observed only after the application of DT. After oral administration, the onset of the effects of CB (30 min) was faster than that of DT (3-4 hr), and the duration of the effects of CB (1-2 hr) was shorter than that of DT (greater than 24 hr).