420 FORMATION OF FAT FROM PROTEIN 



content may be decidedly less than normally. 60 In opposi- 

 tion to this idea K. Landsteiner and V. Muclia 61 have applied 

 themselves with great confidence. As a matter of fact if the 

 whole kidney is not analyzed but the cortex only be used 

 (thus excluding the fat situated about the renal pelvis, which 

 has nothing whatever to do with pathological processes), 

 the microscopic determination and chemical analysis ap- 

 parently agree fairly well. Precise analyses conducted in E. 

 Ludwig's laboratory indicate that while the cortical sub- 

 stance of the kidney may normally contain at most as much 

 as eleven per cent, of fat, this proportion may be much in- 

 creased in phosphorus poisoning. According to Landsteiner 

 it is possible to distinguish two types of renal fatty change, 

 the one a true fatty infiltration (as in the diabetic kidney), 

 and another form in which the fat deposit is associated with 

 distinct cellular destruction. This brings into prominence 

 again the old distinction between fatty infiltration and fatty 

 degeneration. With G. Klemperer 62 one may believe that in 

 the latter process fat phanerosis may also be granted a part. 

 However, sufficient has probably been said to indicate that 

 there is no room left in modern thought for the old accepta- 

 tion of fatty degeneration, that is, that it involves a direct 

 conversion of cellular protein into fat. 



The ability of the kidney to construct fat from its com- 

 ponents, it may be remarked in passing, has been proved by 

 Fischler in the Heidelberg Pathological Institute. He per- 

 fused a living kidney with blood to which soap and glycerine 

 were added, with the production of typical pictures of fatty 

 change of the renal epithelium. 63 



60 G. Rosenfeld, 1. c., pp. 78-81; A. Orgler (Salkowski's Lab.), ibid., 176, 

 413, 1904; E. Kuznitsky (Ribbert's Lab.); Baum and Rosenfeld (Breslau), 

 Berliner klin. Wochenschr., 1909, 629. 



81 K. Landsteiner and V. Mucha (Lab. of Weichselbaum and E. Ludwig, 

 Vienna), Centralbl. f. allgem. Pathol. u. pathol. Anat., 15, 18, 1904. 



93 G. Klemperer (Moabite Hosp., Berlin), Deutsche med. Wochenschr., 

 1909, 89; cf. also Lohlein (Pathol. Instit., Leipzig), Virchow's Arch., 180, 1, 

 1909. 



88 F. Fischler (Arnold's Lab., Heidelberg), Virchow's Arch., 174, 338, 1903. 



