80 E. J. STIEGLITZ 



Siegel (90) confirmed these results. Green (91) also reported a 

 fall (20) per cent) in urinary nitrogen in tubular nephritis when 

 using chromates as the poison. Furthermore, Pearce (92) 

 recorded the disappearance of a distinct depressor substance 

 from the urine in tubular nephritis, but not following glomerular 

 injury, and concluded the retention to be due to the loss of 

 tubular function. Jane way corroborated this by observing a 

 definite fall in blood pressure in acute renal insufficiency. Thus 

 we see that tubular nephritis not only blocks the secretion of 

 iron, but also that of other urinary constituents. 



Group B {tartrate nephritis). That large doses of tartrates, 

 either as the acid or in the form of Rochelle salts, when injected 

 subcutaneously, produce a localized tubular nephritis is well 

 known. Associated with this specific damage there is a diminu- 

 tion of urinary volume and a fall in the secretion of some of the 

 solids (Underbill (93)). The alterations in renal function in 

 tartrate nephritis were further studied by Underbill, Wells and 

 Goldschmidt (37), and they conclude that the administration of 

 alkalies modifies the severity of the reaction. It is a peculiarity 

 of this type of experimental lesions that the severity of the 

 reaction is frequently not in proportion to the dose, although 

 large doses invariably cause a grave reaction. However, with 

 the smaller doses the effects are present, but pass unnoticed when 

 studied merely by routine pathologic methods, for in K22 we 

 found that by the A. 0. B. technique of Bensley (50) the mito- 

 chondria had been profoundly affected, although in routine 

 material the cells looked perfectly normal. 



From a functional point of view the reaction in tartrate 

 nephritis is similar to that of uranium nephritis. With a rela- 

 tively small dose (0.5 gram per 2 kg. body weight) the secretion 

 of iron twenty-four hours later was not much interfered with 

 (K20, K22), but with the severe reaction (2.0 grams subcu- 

 taneously) obtained in K94 only a very slight secretion of iron 

 was recorded. One can conclude, therefore, that these results, 

 associated with the findings in uranium nephritis, further sup- 

 port the conception of secretion of ferric iron by the cells of 

 the convoluted tubules. Similar findings with phenolsulphone- 



