Proteins and Non-protein Colloids as Bioelectric Models.

Abstract

The following experiments were undertaken in order to test the rôle of colloids in the production of electric currents in tissues. Hober and his collaborators, Matsuo, Mond, and Deutsch have tested cell arrangements with various proteins as middle conductors, e. g., 1/10 mol. solution of KCl gelatin, 1/10 mol. solution of LiCl + about 0.01 volt, and compared these with other arrangements in which various animal or vegetable tissue took the place of gelatin. Generally an agreement has been found. It has not yet been shown, however, whether non-protein colloids like agar agar might not act in the same way as proteins. To ascertain this, analogous cells with agar agar, etc., were measured and compared with the protein cells. With protein cells the following electromotive forces have been observed, m/10 KC1 being constantly on the one side of the proteins, 1/10 mol. solutions of various solutions on the other side. This shows that the result of the measurements varies within wide limits. Even for the same protein (gelatin tannate) Matsuo and Mond, both working under Hokr's direction, obtained quite different figures. The range of the electromotive forces observed for all the proteins cited, is given in the following table, and it is to be compared with the electromotive forces observed on agar agar, starch and kaoline. The evidence shows that the values observed on non-protein colloids lie well within the range of the protein electromotive force in every instance. A similar coincidence was observed with various other electrolytes, particularly with methylenbilue and other dyes. In all these cases, agar agar and the other non-protein colloids exhifbited ellectromotive forces resembling closely those of protein cells.