Page:Defensive Ferments of the Animal Organism (3rd edition).djvu/97

 possible. Different observers (Lit. 4, 8, 10, 11, 12, 16, 17, 18, 19), who have instituted experiments on metabolism subsequent to parenteral introduction of proteins, have suggested that decomposition by means of ferments takes place outside the intestines. This is most clearly stated by Heilner. This suggestion, however, was only proved by the direct demonstration of the ferments by means of the experiments and methods we have described.

The positive knowledge that it is possible to induce a splitting activity in the blood plasma of animals, the plasma of which is otherwise unable to decompose albuminous substances, by means of parenteral injections of these substances, led of itself to the problem whether analogous phenomena appear when other substances, which are out of harmony with the body and the plasma, but do not belong to the albumens, are used in such injections. We began with the parenteral introduction of disharmonious forms of sugar. In the first place it was ascertained that the plasma or serum of dogs is unable to split up cane sugar. If blood serum, or blood plasma, of a dog be brought into a solution of cane sugar, it can easily be demonstrated, by means of analytical methods, that the cane sugar does not undergo any alteration. Certainly no decomposition takes place. The contents of the blood plasma are not increased in respect of reduced substances. If,