Nitrogen Metabolism and the Significance of the Non-Protein Nitrogen of the Blood in Experimental Uranium Nephritis

INTRODUCTION It has been known for a long time that, in the course of any nephritis, there are certain periods when the urinary constituents are normal in amount as compared with the intake, and other intervals when they may be increased or diminished. To fathom the reasons for these changes in excretion seemed, until recently, an impossible task. Von Noorden¹begged the question by characterizing the metabolism of nephritis as "bizarre and inexplicable," and many others have followed his example. Observations have been generally based on the assumption that nephritis, whether involving the glomeruli or the tubules, has only one effect on function : a diminished excretory activity of the part. Such an assumption lacks proof and is not in accord with the clinical conditions as they are generally acknowledged to exist. During the past few years the study of these questions has yielded very suggestive results. The following