Chemotherapy of Arsenical Compounds. 149 



essential. Vitamin B has been shown to restore appetite in such 

 animals. 1 The effect of the products on the flow of pancreatic 

 juice and bile was noted in anesthetized dogs in which the pylorus 

 was ligated to prevent secretion due to discharge of acid chyme 

 from the stomach, and the gall bladder bile was prevented from 

 discharging by ligation of the cystic duct. Normal dogs and dogs 

 fed a diet lacking vitamin B were used. It is planned to experi- 

 ment upon polyneuritic dogs as well. Fresh secretin solutions 

 prepared by the usual method were injected as a control. 



Except in the case of tomato juice, all of these products gave 

 negative results. The secretin solutions, however, in compara- 

 tively small amounts always produced a characteristic and vigorous 

 flow. 



72 (1654) 



Theoretical considerations bearing upon the chemotherapy of 

 arsenical compounds. 



By GEORGE W. RAIZISS, JAY F. SCHAMBERG and JOHN A. KOLMER. 



[From the Dermatological Research Laboratories, Philadelphia, Pa.} 



Chemotherapy is essentially the study of the toxic and thera- 

 peutic properties of chemical compounds. Its main purpose is to 

 establish the maximum tolerated and minimum curative doses. 

 The numerical value representing the ratio of these two doses is 

 the chemotherapeutic index. Chemical compounds possessing 

 the highest chemotherapeutic indices in experimental infection 

 are usually the best adapted for the treatment of disease in man. 



Ehrlich, Bertheim and Hata 2 were the first to engage in 

 systematic chemotherapeutic work, in the course of which numer- 

 ous new chemical bodies were synthesized. They were all deriva- 

 tives of one certain compound called atoxyl, selected because it was 

 the only organic arsenical known at that time which possessed 

 trypanocidal properties, although to a very small degree. The 

 changes in the chemical constitution of atoxyl led finally to the 



1 Karr: Jour. Biol. Chem., 1920, xliv, 255. 



2 Ehrlich, P., and Hata, S. "Die Experimentelle Chemetherapie der Spiril- 

 lesen." 



