64 I.O(w\L TISSUE REACTIVITY 



used lor Lhc intravenous injection (^ c.c. per kilo of body weight) . 



The skin-preparatory factors in the hydrogen ion concentra- 

 tions mentioned resisted heating to 60° and 100" c. for one hour 

 but were invariably destroyed by autoclaving at 15 lbs. for forty- 

 five minutes (Shwartzman, 1928^) . 



Bock (1932) studied the effect of hydrogen ion concentration 

 upon the active principles as follows: 



Six quadrants of the al)dominal skin of three rabbits were {pre- 

 pared with B. coli filtrate slightly alkaline, B. coli filtrate neutral 

 to litmus paper, B. coli filtrate acid to litmus paper, sterile broth 

 of pH 7.4, N/10 sodium hydroxide, and N/io hydrochloric acid 

 solutions. One rabbit received a provocative injection of slightly 

 alkaline B. coli filtrate; a second rabbit an injection of B. coli 

 filtrate neutral to litmus paper and a third, a provocative injec- 

 tion of a B. coli filtrate, acid to litmus paper. The first rabbit 

 showed reactions of equal severity in the first three prepared sites 

 and none in the sites prepared Avith sterile broth, N/io sodium 

 hydroxide and N/io hydrochloric acid. The second and third 

 rabbits also gave no lesions in the latter three sites and only 

 weak reactions in sites prepared with B. coli filtrate at various 

 reactions. In another group of experiments the preparatory in- 

 jections of B. coli filtrate of pH 7.4, 5.5, and 8.5 were made. One 

 of the rabbits received a provocative injection of B. coli filtrate 

 of pH 5.5 and another of the filtrate of p?I 8.5. The rabbits re- 

 ceiving provocative injection of filtrate of pH 7.4 and 8.5 gave 

 uniformly severe reactions in the three prepared sites, whilst the 

 rabbit receiving injection of the filtrate of pH 5.5 gave no re- 

 actions. 



This author concluded from his experiments that the potency 

 of the reacting factors is inhibited by an acid reaction. On the 

 other hand, the hydrogen ion concentration seemed to have no 

 effect upon the skin-preparatory potency of the filtrate. 



DeCour (1934) precipitated active filtrates with acetic acid of 

 pH 4.7 and redissolved the coagulum in sodium hydroxide of pH 

 7.5. The redissolved coagulum became completely inactive. He 

 does not state wdiether the coagulum ^vas tested for skin-prepara- 

 tory or reacting potency. 



Stolyhwo (1935) investigated the effect of storage under various 

 conditions iq^on the activity of the filtrates, i.e., filtrates exposed 

 to light, stored at room temperature, and incubated at 37° c. in 



