Concerning the amount and distribution of stainable lipoid material in renal epithelium in normal and acutely nephropathic animals,with observations on the functional response of the kidney

Conclusions

1. Lipoid material stainable with Scharlach R. is constantly found in the cells of the loops of Henle in normal dogs. The presence of such material in this location is not indicative of a pathological kidney. The functional capacity of such a kidney is normal.

2. When animals are given one subcutaneous injection of 6 mg. of uranium nitrate per kilogram, the earliest evidence of injury to the kidney consists of an increase in the amount of stainable lipoid in the cells of the loops of Henle. At this stage of the intoxication there is no evidence of a functional disturbance on the part of the kidney and no change takes place in the acid-base equilibrium of the blood.

3. At a later stage of such an intoxication (12 hours) stainable lipoid material appears in the convoluted tubule epithelium. The vascular tissue of the kidney is uninjured. Associated with such a disturbance in the metabolism of these cells that leads to the appearance of stainable lipoid in the cell there occurs a reduction in the elimination of phenolsulphonephthalein, a depletion in the alkali reserve of the blood and the appearance of albumin and glucose, or glucose alone in the urine.

4. Following this initial injury to the tubular epithelium changes of a more distinctly degenerative type appear in these cells and the functional capacity of the kidney is more severely impaired.