Nitrogen and sodium chloride excretion in experimental uranium nephritis. 1

Abstract

A series of experiments were performed upon dogs with the object of determining the effects on the output of nitrogen and sodium chloride in nephritis produced by the subcutaneous injection of uranium nitrate. These dogs were fed the usual standard diets, also diets containing much meat, as well as food to which considerable amounts of urea and sodium chloride had been added.

The results of these experiments appear to justify the following conclusions regarding uranium nephritis.

1. The nitrogen secreted by the small intestine, as determined by the Thiry fistula method, is somewhat diminished.

2. The fecal nitrogen remains approximately unchanged.

3. The urinary nitrogen is not diminished even when the diet demands an excretion of one gram of urinary nitrogen per kilo of body weight of the dog.

4. In some cases the urinary nitrogen is increased. The source of this excess of nitrogen is problematical. It may be due to protein destruction of the body tissues caused by the same toxic agent as the nephritis. If this be true, the “rest” nitrogen of the blood serum should be higher than normal. Experimental attempts have been made to ascertain the facts in this connection but have not been pushed far enough to warrant a definite statement.

5. The sodium chloride excretion in the urine keeps pace with the intake even when considerable quantities are added to the food.

6. The above statements have held true for dogs after the first as well as after several large single injections of the drug at long intervals. One animal was tested after he had received as many as seven injections.