Abstract

The following is a resumé of the pharmacological study with the six principles isolated from Ch`an Su:

1. Cholesterol is admixed with ergosterol, containing two parts of the latter per thousand, as proved both spectroscopically and biologically.

2. Epinephrine has all the known properties of the hormone produced by the suprarenal medulla.

3. Cinobufagin possesses the essential features of the members of the digitalis group, as shown by the myocardiogram, electrocardiogram, and the emetic action. Its m.s.d. in frogs is 0.02 mgm. per gram. This figure probably does not represent the true potency of this compound, since it is slightly soluble and difficultly absorbed. Its minimal emetic dose in pigeons is 0.3, that in cats 0.125, and the average fatal dose in cats is 0.23 mgm. per kilogram. Its cardiac action is not persistent. It has a local anesthetic effect, exerts a stimulating action, followed by a depression, on the medulla in frogs, and increases the tone of the smooth muscles of the blood vessels, intestines, and uterus.

In a few cases of auricular fibrillation in men, 1.0 mgm. of cinobufagin injected intravenously caused a prompt fall of ventricular rate, lasting for few hours.

4. Cinobufotoxin has an action similar to that of cinobufagin. Its m.s.d. in frogs lies between 0.0075 to 0.01 mgm. per gram. This is probably underestimated on account of the difficult absorption of the compound. The minimal emetic dose of cinobufotoxin in pigeons is 0.2, in cats 0.125, and the average fatal dose in cats 0.35 mgm. per kilogram. The substance is also rapidly eliminated. It has a stimulating action on the smooth muscles of the blood vessels, intestines, and uterus, but causes no local anesthetic effect nor fibrillatory movements and convulsions in frogs.

5. Cinobufotenine in the form of the flavianate has a marked pressor action owing to vasoconstriction and cardiac stimulation, its activity being equivalent to about one-tenth that of epinephrine chloride. It increases the tone of the isolated intestines and uterus. When applied locally to the eyes of rabbits and cats, it has a slight miotic action.

6. Suberic acid is relatively much less active. It inhibits the contractions of the isolated intestines and uterus.