1912.] The Metabolism of Lactating Women. 91 



involute, excreted much larger quantities of creatin. It would be unfair 

 to press the interpretation of these experimental figures too far, because I 

 think the excretion of creatin following a Caesarian section may not be 

 completely analogous to that accompanying a normal pregnancy. For 

 instance, the following figures show that, even after an abdominal 

 hysterectomy for uterine fibroids, creatin is excreted : — 



Abdominal Hysterectomy. Fibroids of Uterus. 



Time after 



Creatin in 



Creatinin in 



Creatin 



operation. 



10 c.c. 



10 c.c. 



Creatinin 





rngrm. 



mgrni. 



0-7 



18 hours 



9-9 



14 -0 



4 days 



16 



12-8 



1 25 



8 „ 



4-3 



9-6 



0-45 



It may further be stated that all abdominal operations result in the 

 excretion of some, but very variable amounts of creatin. The significance of 

 this fact will be considered elsewhere.* 



As regards the Caesarian section figures two points are worthy of mention. 



(1) Although such large amounts of creatin were excreted, the creatinin 

 excretion was normal or but little diminished. In other words, the large 

 creatin excretion was not produced at the expense of the creatinin. For 

 instance, Case B excreted 2 - 86 grm. of (creatin + creatinin) per diem on 

 an average over three days, whereas in normal health such a woman would 

 excrete but little more than 1 grm. of creatinin and no creatin. This point 

 is important, because it is commonly said that creatin is converted into 

 creatinin, probably by the liver, and also that an increase of creatin 

 excretion is accompanied by a diminution of creatinin. This relation may 

 possibly hold in conditions like inanition, and in the absence of carbo- 

 hydrate (Cathcart, 7) from the diet, for in such conditions there is usually 

 a diminution of creatinin excreted, together with an increase of creatin. 

 But it does not hold in the above cases of Caesarian section. 



(2) The creatin excretion following Caesarian section did not depend on 

 inanition or absence of carbohydrate from the diet. Both patients were 

 taking an adequate amount of food throughout the period of examination 

 and the urine did not indicate any condition of acidosis. 



To sum up, there is no evidence that the puerperal creatin excretion 

 depends, to any extent, on the involution of the uterus. 



* In the meantime I should like to utter a warning with regard to the interpretation 

 of experiments on creatin metabolism which involve opening up the abdominal cavity. 



