170 LOUIS BAiniAX 



Urine. Under normal conditions creatin is absent from the urine of 

 men when living on a creatin free diet; it is constantly present in the 

 urine of children and frequently occurs in the urine of women. Powis 

 and Raper have shown that children eliminate more creatin during the 

 day than at night. In the young the supply of carbohydrate and fat 

 appears to be unable to meet the demands of growth and maintenance, 

 and as a consequence muscle tissue disintegrates, creatin is liberated and 

 appears in the urine. The frequent occurrence of acetonuria in children 

 and the rapidity with which the glucose content of their blood is lowered 

 during starvation are further indications of a limited supply of glycogen 

 (Sawyer, Stevens and Bauman). The occurrence of creatin in the urine 

 of children may also be due to a diminished ability to destroy it (Krause 

 (&), 1913; Gamble and Goldschmidt (a), 1919). In infants the in- 

 creased excretion of creatin when they are on a pure milk diet may be due 

 to the creatin present in the milk and not to the protein therein (Gamble 

 and Goldschmidt (6), 1919). 



Sawyer, Stevens and Bauman observed that the increased excretion of 

 creatin which occurs in children when deprived of carbohydrates is usually 

 followed by a period of creatin retention upon resumption of the normal 

 diet. It appears as if the body retained creatin with great regularity 

 under these circumstances. 



The alleged occurrence of creatinuria after menstruation (Krause (a), 

 1911) has not been confirmed by M. S. Rose, who found no definite rela- 

 tion between the creatin output and the sexual cycle, nor was creatin 

 excretion affected by protein feeding. In normal pregnancy the excretion 

 of creatin is usually less than 20 per cent of the creatinin excretion (Van 

 Hoogenhuyze). A pregnant woman excretes about 170 mgs. of creatin 

 and the same woman during the lying-in period eliminates about 470 mgs. 

 (Van Hoogenhuyze and ten Doeschate). After cesarean section an in- 

 creased elimination of creatin occurs even when the uterus has been re- 

 moved at the time of operation (Mellanby (5), 1913 ; Morse). F. G. Bene- 

 dict (c), and F. G. Benedict and Diefendorf first noted the occurrence of 

 creatin in the urine of starving men and women. Mendel and Rose (a) 

 (1911) found creatin in the urine of adult animals when they were de- 

 prived of carbohydrates and began to break down their body proteins. 

 Certain animals having small reserves of glycogen and fat, as the rabbit, 

 will excrete creatin after a short fast, while others with large stores of fat } 

 as the pig, can be fasted for from 14 to 16 days without excreting creatin 

 (McCollum and Steenbock)! In this respect the human being and dog 

 occupy intermediate positions. Mendel and Rose (a) (1911) found that 

 rabbits began to excrete creatin on the second day of starvation and that 

 the amount excreted gradually rose until death. Depriving the tissues of 

 carbohydrates by means of phlorhizin poisoning also leads to creatinuria 

 (Mendel and Rose (a), 1911; Cathcart and Taylor). 



