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Scientific Proceedings (132) 



220 (2180) 



Diet and tissue regeneration. 

 By ARTHUR H. SMITH and T. S. MOISE. 



[From the Sheffield Laboratory of Physiological Chemistry and 

 the Department of Surgery, Yale University, New Haven, Conn.] 



Two types of diets were used : one, containing casein as the 

 protein, and being adequate for normal growth ; the other, having 

 gliadin as the protein, sufficing for maintenance but not for 

 growth. Both foods provided 5.3 Cals. per gram and were iden- 

 tical in their composition except for the difference in quality of 

 the protein. 



White rats of similar ages were employed. A standard tissue 

 damage (liver necrosis) was induced by subcutaneous injection 

 of 1 c.c. sterile mineral oil containing 0.15 c.c. chloroform per 

 100 grams body weight, which had been previously determined 

 to be the maximum non-lethal dose. The animals were killed 

 at definite intervals, a control rat on standard food together 

 with an experimental rat on gliadin food. 



This procedure produces a necrosis of the liver cells around 

 the central vein of the lobule appearing at its maximum 24 to 

 48 hours after the injection. In both series of rats there occurs 

 an early mobilization of leucocytes and clearing away of the 

 cellular debris with a simultaneous initiation of regeneration 

 from the uninjured cells at the periphery of the lobule. The 

 process of repair is most active at about 72 hours after the in- 

 jection in both series. At 120 to 148 hours the regeneration is 

 apparently complete and the liver is histologically normal. 



The rate of procedure of the repair, so far as we have been 

 able to observe, is the same for both groups of animals. This 

 fact raises the question as to the possibility of such repair in- 

 volving, as it does, tissue reconstruction upon the gliadin food — 

 a diet upon which general body growth is impossible. A dis- 

 cussion of the application of these results to the theories of 

 intermediary protein metabolism will be reserved for a later 

 publication. 



