MECHANISM OF RENAL SECRETION 77 



Leyden, Mann, and Councilman, all report large series of acute- 

 nephritis cases which are followed by a quiescent period of sev- 

 eral years and later the appearance of a chronic form of nephritis 

 responsible for death. These, however, were of infective origin. 

 Dickson (34) was able to reproduce chronic nephritis with pro- 

 longed administration of uranium nitrate. 



However, from the point of view of the present investigations 

 on the mechanism of renal secretion, the acute nephritides are 

 the important class. They may be divided into those in which 

 tubular damage plays the essentially important role and those 

 in which the glomeruli are chiefly interfered with. Thus we speak 

 of a 'tubular' and 'glomerular' or 'vascular' nephritis (83). These 

 two types of lesions we may produce at will. However, the 

 terms are merely relative, and in the glomerular nephritis there 

 is undoubtedly some slight degree of tabular injury. The cause 

 for the different localization of the deleterious effects of the 

 various poisons used is that the lesions undoubtedly occur in 

 that part of the uriniferous apparatus through which they are 

 eliminated; the reaction of a cell to an intracellular poison is 

 many times more violent than if the cell were merely bathed in 

 an extremely dilute solution of the same poison. 



Glomerular nephritis may be produced with arsenic, canthar- 

 idin, diphtheria toxin, or snake venom. Arsenic paralyzes the 

 capillaries, causing marked functional changes with little or no 

 anatomic evidence thereof. Catharidin causes a reaction both 

 in the tuft and the capsular wall; from the latter there is con- 

 siderable desquamation, and the convoluted tubules are also 

 damaged. Diphtheria toxin causes the production of hyalin 

 thrombi in the glomerular tuft and some necrosis there, with a 

 mild degeneration noted in the convoluted tubules. The typical 

 tubular nephritis is produced by uranium salts, mercuric bichlo- 

 ride, chromates, and tartrates, the latter in large doses. It is 

 with the tubular form that we are concerned. Aschoff (28) and 

 his student Suzuki (29) have carried the work on locahzation of 

 the poisonous effects one step further, and claim that the con- 

 voluted tubule may be divided into three portions, each reacting 

 quite specifically to certain poisons. This remarkable special- 



