TY - JOUR T1 - THE PHYSIOLOGICAL ACTION OF THE PRINCIPLES ISOLATED FROM THE SECRETION OF THE JAPANESE TOAD (BUFO FORMOSUS) JF - Journal of Pharmacology and Experimental Therapeutics JO - J Pharmacol Exp Ther SP - 26 LP - 35 VL - 49 IS - 1 AU - K. K. CHEN AU - H. JENSEN AU - A. L. CHEN Y1 - 1933/09/01 UR - http://jpet.aspetjournals.org/content/49/1/26.abstract N2 - From the "parotid" secretion of the Japanese toad, Bufo formosus, the following principles have been isolated and studied pharmacologically: a. Cholesterol, which is admixed with very little or no ergosterol. b. Gama-bufagin, C27H38O6, which has a digitalis-like action. The minimal emetic dose in pigeons is 0.15 mgm., that in cats 0.07 mgm., and the average fatal dose in 10 etherized cats 0.1 mgm. per kilogram. c. Gama-bufotoxin, C41H64O11N4, which also has a digitalis-like action. The minimal emetic dose in pigeons is 0.20 mgm., that in cats 0.175 mgm., and the average fatal dose in 10 etherized cats 0.38 mgm. per kilogram. Both gama-bufagin and gama-bufotoxin have a pressor action and stimulate isolated intestines and uteri. d. Gama-bufotenine, in the form of a flavianate, C12H1802N2.-C10H6O8N2S, which is an indole derivative. It has an average of 89 per cent of the pressor activity of cino-bufotenine flavianate. It increases the tone of cardiac contractions in frogs and stimulates isolated intestines and uteri. Evidence has also been obtained, both chemically and physiologically, of the presence of epinephrine in the secretion. ER -