On the production of hyaline casts by certain ions

At the February meeting of this Society one of us (G.) reported that after an intravenous or intramuscular injection of a sublethal dose of a solution of megnesium sulphate in dogs hyaline casts invariably appear in the urine. As a result of this observation a series of experiments was made to answer the question as to which of the ions of the injected salt is the cause of the appearance of the hyaline casts—the kation magnesium, or the anion SO₄, the sulphate radical. We have tested in the first place several magnesium salts as well as several sulphates. This led up to further experimentation with some salts which contain neither magnesium nor the sulphate radical. Briefly stated, our results are in general as follows: The injection of any compounds which have either magnesium or the sulphate radical as a component caused the appearance of hyaline casts in the urine. The injection of salts which had in their composition neither Mg nor SO₄, produced, however, no such effect. Of the magnesium salts, besides the sulphate, the chlorid, nitrate and the acetate were studied also. They all caused the appearance of hyaline casts in abundance. The acetate was perhaps less effective. Of the sulphates, besides the magnesium, also the salts of sodium, ammonium, and potassium were studied. All gave hyaline casts; the action of potassium, however, was less transparent. On the other hand the chlorids of sodium and of ammonium and the nitrate and the acetate of sodium produced no hyaline casts. The effects of potassium salts were apparently complicated by the profound action of these salts upon the heart and probably also by some direct action upon the kidneys. Of course, we could not attempt to give here any further details, nor enter upon a theoretical discussion of the possible significance of the reported facts.