Scientific Proceedings. 



39 



Seventh meeting. 



Physiological Laboratory of the New York University and Belle- 

 vue Hospital Medical College. May 18, igo/f.. 



39. " The lecithin content of fatty extracts from the kidney " 

 (preliminary communication) : EDWARD K. DUNHAM. 



Rosenfeld has shown that the percentage of the alcohol-chloro- 

 form extracts from the dried kidneys of dogs, both normal and 

 " fatty," fluctuates within very narrow limits. He calls these ex- 

 tracts " fat," and regards the microscopic examination as entirely 

 untrustworthy for gauging the amount of fat in the kidney. His 

 work on other organs has led him to the conclusion that, when the 

 fat content is increased in the cells, it has been transported from the 

 fat depots of the body. It appeared to the author of interest to 

 compare the extracts obtained from the kidney by Rosenfeld's 

 method with similar extracts from the depot fats. It was at once 

 evident that they differed markedly in the percentage of phosphorus 

 they contained, as is shown by the following analytic results : 



The extract from the kidney contains from 200 to 500 times 

 as much phosphorus as the extract from depot fat. These facts 

 suffice to show that the two extracts are not directly compar- 

 able, and to throw doubt upon the idea advanced by Rosenfeld that 

 the fat in "fatty" organs is a simple infiltration from the depots of 

 the body. 



The phosphorus in these extracts was found to be wholly 

 organic in character. Protagon could not be detected even in 400 

 gms. of the tissue. The quantity of jecorin that may have been 

 present was too small to influence materially the analytic re- 

 sults. The most probable compounds containing the phosphorus 

 are forms of lecithin. The barium hydroxid — platinic chlorid 

 method for the separation of cholin was employed, with the fol- 

 lowing results : 



1 Reprinted from Science, 1904, xx, p. 79 ; American Medicine, 1904, vii, p. 950 ; 

 Medical News, 1904, lxxxv, p. 230. 



Alcohol-chloroform extracts. 

 Human kidney (mean of 28 analyses) 

 Panniculus adiposus (4.2288 gms.).... 

 Perinephritic fat (5.6750 gms.) 



Percentage of 

 Phosphorus. 



I.3849 



O.OO26 

 O.O069 



