FORMATION OF FAT FROM PROTEID 297 



The deposit of fat in the liver cells begins in the peripheral 

 part of the lobules, where the connection with the blood stream is 

 closest. The same results have been obtained on starved fowls, and 

 on rabbits in which the diphtheria toxin was used as the poisoning 

 agent. Kraus and Sommer have determined that the total fat in 

 white mice is not increased by phosphorus poisoning but de- 

 creased, and even to the extent of one-half. 



In opposition to these results is the fact that phosphorus 

 produces abundant signs of proteid decomposition, viz. the presence 

 of lactic acid, tyrosin, leucin in the urine, &c. These substances 

 all contain less nitrogen than proteid lactic acid 0, leucin 10*67, 

 tyrosin 7*77 ; but we have no evidence of the excretion of the 

 whole of the non-nitrogenous residue of the decomposed proteid, 

 and can formulate no reasonable hypothesis of its fate except that 

 of its becoming fat. Thus Bauer executed a metabolism research on 

 a dog which had fasted twelve days, and to which he administered 

 small doses of phosphorus. The N 2 output doubled while the 

 C0 2 output and 2 intake sank to one-half, which suggests that 

 much of the non-nitrogenous moiety of the decomposed proteid 

 remained in the body. The dried liver substance of this dog 

 yielded 30 per cent, of fat, while the normal is about 1O4 per 

 cent. ; the dried muscles 42 -4 per cent., while the normal is about 

 16'7 per cent. This observation and those of Rosenfeld and his 

 school appear at present, therefore, to be in direct antagonism. 



Arsenic, antimony, phloridzin, alcohol, and many other 

 poisons, such as CO and bacterial toxins, cause infiltration of the 

 tissues with fat. 4 c.c. per kilo of alcohol fed to fasting dogs 

 produces a fatty liver. 



Rosenfeld obtained the same results with phloridzin as with 

 phosphorus. 



Mutton-fatted dogs gave mutton fat in their livers on giving 

 2 grm. of phloridzin per kilo. No fat accumulated in the livers of 

 dogs starved to the utmost. In fasting animals the proteid is 

 decomposed by phloridzin, and the non-nitrogenous moiety ex- 

 creted as sugar, so that the fat cannot be derived from proteid in 

 this case. 



Fatty infiltration of the organs is produced by keeping animals 

 in an over-heated atmosphere the livers of geese are thus 

 prepared for pate de foie gras. The same thing coupled with 

 rickets has been observed in high stud foals whose dams have 



