Originally publishod in Xaturc, 140, 275 (1!)37) 



28. LECITHINAEMIA FOLLOWING THE 

 ADMINISTRATION OF FAT 



G. Hevesy and E. Lundsgaard 

 From the Institute of Theoietical Physics and the Physiological Insi i1 ute. University 



of Copenhagen 



About two hours after tht^ administration of a meal containing fat. 

 the fat content of the blood begins to rise. Bloor^ found that when olive 

 oil is administered to a dog, besides an increase in the neutral fat content 

 of the blood an increase in its lecithin content also takes place. The 

 average increase was found to be about 20 per cent. A maximum is 

 reached after four hours. Bloor was inclined to ascribe the lecithin formed 

 after the administration and resorption of the neutral fat to a synthesis 

 occurring inside the red blood corpuscles. Other explanations might, 

 however, be suggested as well, namely: (1) The lecithin is synthesized 

 in the intestinal mucose and resorbed into the blood. (2) The synthesis 

 takes place, after the resorption of neutral fat, in the liver, or some- 

 where else outside the intestinal tract. (3) The increase in the lecithin 

 content of the blood is due to mobilization of preformerl lecithin aftci 

 the resorption of the neutral fat. 



To decide which of these suggestions is to be accepted we repeated 

 Bloor's experiment, but administered simultaneously with the oil- 

 labelled (radioactive) phosphorus in the form of sodium phosphate. In 

 the case denoted by (1) the additional blood lecithin should contain 

 chiefly labelled phosphorus; in case (2) the additional lecithin should 

 contain only small amounts of labelled phosphorus; in case (3) the ad- 

 ditional lecithin should contain ordinary phosphorus only. 



We determined the normal P present in the blood lecithin, which was 

 extracted by the usual procedure, by the method of Fiske and Subbarow, 

 and the labelled P by means of a Geiger counter. While, as seen in the 

 table, the lecithin phosphorus content of 100 cc. of blood increased by 

 2 mgm four hours after administering the oil, that of labelled P only 

 increased by 0.096 mgm. We must, furthermore, take into account the 

 fact thai half the labelled phosphorus administered two hours before 

 Ihe oil pr'oduced 0.028 mgm labelled lecithin P during that time. We 

 must ther-efore deduct 2 x 0.028 mgm IVom the 'oil effect" of 0.096 mgm. 

 obtaining r).04 niL'^m per 100 cc. ol hlood foi' th(^ maximuni vahie of the 

 'oil clfect". 



