PROTEIN REGENERATION 33 



paper (393) he confirmed his original finding and adduced additional 

 experimental evidence. Brailsford Robertson (337, 338) found that 

 by the action at 40 C. of a concentrated solution of pepsin on an acid 

 concentrated solution of the products of peptic digestion of caseinogen 

 a substance was precipitated within a few hours which was identical 

 in properties and phosphorus content with a substance related to para- 

 nuclein. This material was only formed by the action of the pepsin 

 on the caseinogen digest, since if both these substances were kept 

 separate under similar experimental conditions no precipitate was 

 formed. 



The R61e of the Leucocyte. 



Another view of the process by which protein digestion products are 

 dealt with after absorption has been put forward by Hofmeister (197). 

 He believed that the peptone after absorption was taken up by the leuco- 

 cytes and then either through their own agency or through that of the 

 adenoid tissue it was converted into protein. This contention was largely 

 based on the marked leucocytosis which was found to occur after a 

 meal and not on the direct estimation of the contents of the leucocytes. 

 In support of this hypothesis of Hofmeister, Pohl (332) found that dur- 

 ing digestion, in addition to the postprandial leucocytosis, there was 

 an excess of leucocytes in the mesenteric veins as compared with the 

 mesenteric arteries. Paton, Goodall and Gulland (321) showed that 

 there was no detectable difference between the number of white cells in 

 the veins and the arteries. They, however, confirmed the postprandial 

 leucocytosis and showed that the most marked percentage increase 

 occurred in the lymphocytes. There was also some increase in the 

 polymorphonuclears but practically no change in the number of the 

 eosinophiles. The maximum increase in the number of the leucocytes 

 took place about four hours after food. Paton and Goodall (322) later 

 demonstrated that the leucocytes did not arise in the intestinal lymphatic 

 tissue as Hofmeister believed, but that they orginated in the bone- 

 marrow. Erd61y (120) also worked at this problem and found that 

 the intestinal wall was richer in leucocytes after a meal than after a 

 period of starvation. He believed that alterations in the nature of the 

 diet brought about variations in the nature of the leucocytosis. Cramer 

 and Pringle (100) have also supported the hypothesis that the leuco- 

 cytes played a very important part in the assimilation of the protein 

 food products from the intestine, and Cramer (99) believes that even in 

 the case of protein introduced parenterally assimilation is the result 



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