July 3. 1916 Effect of Autolysis upon Muscle Creatin 545 



Fine (5). Mellanby (4) obtained contrary results; but, as has already 

 been noted, a careful examination of his paper indicates something 

 wrong with his work, since he was unable to detect creatinin under con 

 ditions in which it was undoubtedly present. His findings should not 

 be taken too seriously. The ability of autolyzing muscular tissue, as well 

 as of other body tissues, to transform creatin into creatinin seems to be 

 quite clearly established. 



In the aseptic autolytic experiment there was first an increase in 

 total creatinin and later a decrease as compared with the amount present 

 in the fresh material, while in the experiment carried on under antiseptic 

 conditions there was practically no change. As has been previously 

 noted, it does not follow that the results of the first experiment are in 

 error, but it is possible that in the second experiment the presence of 

 antiseptics prevented these changes in creatin. 



A brief examination of the work of previous investigators on this 

 point may throw some light on the question. Gottlieb and Stangas- 

 singer (3) observed at first an increase and later a decrease in the total 

 creatinin content of muscular and other body tissues and fluids on 

 autolysis. Stangassinger (9) found an increase in the total creatinin 

 content of blood and liver of dogs and later a decrease in the total 

 creatinin content of the liver. Rothmann (7) found that extracts of the 

 liver and kidney of dogs destroyed added creatinin in a marked degree, 

 and that there was a marked increase in the creatin content of the portal 

 blood of a dog. Rowe (8) observed that extracts from the parathyroid 

 and adrenal glands of sheep destroyed added creatin. Pekelharing and 

 van Hoogenhuyze (6) found an increase in the creatin content of the 

 muscles of dogs after rigor mortis and heat rigor. Myers and Fine (5) 

 found an increase in the total creatinin content of autolyzing human 

 blood and rabbit liver, and a decrease in the total creatinin content of 

 dog muscle. On the whole, the work of these investigators confirms our 

 findings concerning changes in the total creatinin content of beef muscle 

 during aseptic autolysis. 



In keeping with the results obtained by Pekelharing and van Hoogen- 

 huyze (6) concerning the effects of rigor mortis upon the creatin content 

 of muscular tissue, it seems very probable that the increase in the total 

 creatinin content of the muscle in our aseptic autolytic experiment .was 

 due to the changes accompanying rigor mortis. While analytical work 

 was started 24 hours after the slaughter of the animal, at which time rigor 

 was assumed to be complete, yet in a study of the effects of autolysis 

 upon the soluble muscle proteins changes were observed which indicated 

 that it was not complete at that time. 



The establishment of an equilibrium between creatin and creatinin in 

 solutions of the individual bases, as observed by Myers and Fine (5), 

 and our finding as to the establishment of a similar relation between 

 creatin and creatinin in autolyzing muscular tissue, is a matter of more 



