PAPERS ON PSYCHOLOGY AND PHYSIOLOGY 135 



EVIDENCE THAT CATALASE IS THE ENZYME 



IN ANIMALS AND PLANTS, PRINCIPALLY 



RESPONSIBLE FOR OXIDATION. 



W. E. BuEGE, Univeksity of Illinois 



We have found that whatever increases oxidation in 

 the animal produces an increase in catalase, an enzyme 

 possessing the property of liberating oxygen from hydro- 

 gen peroxide, by stimulating the alimentary glands, 

 particularly the liver, to an increased output of this 

 enzj^ne, and whatever decreases oxidation produces a 

 decrease in catalase by diminishing its output from the 

 liver and by direct destruction. 



The food materials were found to stimulate the liver 

 to an increased output in catalase parallel vdth the in- 

 crease they produce in oxidation, the proteins being more 

 effective in this respect than the fats or carbohydrates, 

 in keeping with the fact that protein is more effective in 

 increasing oxidation. The ingestion of saccharin was 

 found to increase catalase and in this Avay may serve as 

 a food material. 



In exophthalmic goiter, a disease in which there is a 

 h^-persecretion of the thyroids, it is kno^Ti that there is 

 a great increase in oxidation in the body. We found that 

 when desiccated thyroid is fed to an animal, it stimulates 

 the liver to an increased output of catalase, which sug- 

 gests that the increased oxidation in exophthalmic goiter 

 may be due to the increase in catalase brought about by 

 the hypersecretion of the thyroids. It was also found 

 that the catalase content of the tissues was greatly de- 

 creased in diabetes, a disease in which oxidation is de- 

 fective. The decrease in this enzyme may be the cause of 

 the defective oxidation. 



The narcotics were found to decrease catalase par- 

 allel with the decrease they produce in oxidation by di- 

 minishing the output of this enzyme from the liver and 

 by direct destruction, A strong narcotic, such as chloro- 

 form, was more effective in this respect than a weaker 

 narcotic, such as ether. A rapidly acting narcotic, such 

 as nitrous oxide, decreased catalase very quickly, while 



