205 



The Alleged Excretion of Creatine in Carbohydrate Starvation. 



By George Graham, Beit Memorial Fellow, and E. P. Poulton, Kadcliffe 



Travelling Fellow. 



(Communicated by Dr. F. G. Hopkins, F.R.S. Received August 5,— 

 Read November 20, 1913.) f 



(From the Pathological Department, St. Bartholomew's Hospital, and the Physiological 

 Department, Guy's Hospital.) 



CONTENTS. 



PAGE 



Introduction 205 



L The Effect of Aceto-acetic Acid on the Estimation of Creatinine 206 



II. A Method for Kemoving Aceto-acetic Acid from Urine preliminary 



to the Estimation of Creatinine 212 



III. The Alleged Excretion of Creatine on a Carbohydrate-free Diet 216 



Introduction. 



It was stated by Cathcart (4) and Benedict and Myers (2) independently, 

 in 1907, that creatine was excreted in the urine during inanition. Cathcart (5) 

 has further stated that the output of creatine, caused by fasting for 36 hours, 

 is diminished as soon as a diet consisting of carbohydrates is taken, whereas 

 it is increased by a fat diet. 



Rose and Mendel (19) confirm these results, laying great stress on the fact 

 that carbohydrates play a very important role in preventing the excretion of 

 creatine in the urine. 



In the course of a 10 days' experiment on one of us (G. G., 10), where the 

 diet was restricted to protein and fat and was of insufficient calorie value, we 

 found that no creatine was excreted in the urine. The explanation of this 

 discrepancy was not fully investigated at that time, but recent work by 

 Green wald (12) has suggested a possible explanation. 



Folin's (8) method for the estimation of creatinine in urine depends on the 

 orange colour produced by the addition of picric acid and soda (Jaffe\ 15). 

 This colour has been shown to be due to a reducing action of the creatinine 

 on the picric acid (Chapman, 6). 



Among the reducing substances which also give a similar colour are 

 acetone, aceto-acetic acid, and y8-oxybutyric acid, all of which maybe present 

 in urine under different conditions. 



Van Hoogenhuyze and Verploegh (13) and Krause (16) stated that urine 

 to which acetone had been added produced, with picric acid and soda, a 



vol lxxxvii. — B Q 



