The Action of '" Peptone " on Blood and Immunity thereto. 379 





Control 

 plasma 



on 

 paraffin. 



-6 p.c. 

 peptone 

 plasma on 

 paraffin. 



-9 p.c. 

 peptone 

 plasma on 

 paraffin. 



1 - 2 p.c. 

 peptone 

 plasma on 

 paraffin. 



Time of " commencement." of clotting ... 





 15 

 23 50 



/ // 





 34 45 

 41 45 



18 



/ // 

 



50 20 



51 20 

 19 



/ // 

 

 24 30 

 30 

 20 



Notes. 



1. Eepetition of Nos. 18 and 19 gaye the same results. 



2. In No. 20, after 20 minutes the gel appeared to liquefy, due probably to syneresis. 



3. Plasma was obtained from animal respiring air. 



more prone to coagulate rapidly than that of pithed animals 15 minutes after 

 respiring only air. For this reason, except for the experiments cited above, 

 all observations not on pithed animals were discarded. 



In both the last two series of experiments typical syneresis was exhibited 

 in the clots formed. The view that blood platelets are necessary for the 

 production of syneresis (Bordet and Delange, 45) may be mentioned. 



The Influence of Speed of Injection on the Action and Imm,unity to the Action 



of Peptone on Blood. 



Fano (46) found that, if " peptone " is injected slowly into the circulation, 

 it has not any anticoagulant action on the blood, and later Nolf (Joe. cit.) 

 showed the concentration of " peptone " as well as the speed of its injection 

 to be the determining factors either in the production of anticoagulant action 

 or complete or partial immunity thereto. Nolf explained the immunity 

 following minimal doses injected rapidly and larger doses injected slowly by 

 suggesting that leucocytes are not acted upon by " peptone " if delivered 

 sufficiently slowly, and that they become accustomed to increasing doses. The 

 leucocytes, he believes, under these conditions fail to produce the unknown 

 substance which stimulates the liver to secrete either antithrombin or 

 fibrinolysin. The experiments described in the preceding section demon- 

 strate that leucocytes are not essential for the production of the anti- 

 coagulant action of " peptone " in vitro, and there appears to be no valid 

 reason for assuming their presence to be necessary for the production of the 

 same effect in vivo, when the concentrations are strictly comparable. 



In sharp distinction to the generally accepted view is that of Mellanby (47), 

 who maintained that fluidity of peptone blood is due to the secretion of an 

 excess of alkali by the liver, under the influence of a stimulus of injected 

 " peptone," and the " peptone " immunity is caused by the temporary dis- 



