PREVITE AND BERRY 



Days Post 50ug 2 Units ACTH 8 Units ACTH 8 Units 

 Infection LPS 6 50ug LPS & 50ug LPS ACTH 



30 

 15 

 15 



50.0 10.0 100.0 



Table VTII. Sensitization to Lipopolysaccharide by ACTH. Treatment antl survivors. 



suits indicate that this does occur (Table VIII). Two or eight units 

 of ACTH were administered subcutaneously immediately before 

 50 Mg of lipopolysaccharide and subsequent exposure to 5 C. 

 Survival in controls (63.3 per cent) was slightly but not significantly 

 higher (P>0.05) than that of animals receiving 2 units of ACTH 

 (50 per cent), but was significantly higher (P<0.001) than that in 

 animals receiving 8 units of this hormone (10 per cent survival). 

 Eight units of ACTH alone did not kill any of 14 mice. 



DISCUSSION 



Following experimental infection with S. typhimurium , the 

 greater susceptibility of cold exposed mice (5° C, measured in terms 

 of both survivorship and survival time) compared to those main- 

 tained at usual room temperature (25° C) is evident only when a 

 comparatively avirulent strain is used (SR-U-A), Thus, a situation 

 in which the outcome of a host- parasite interaction is intimately 

 linked to the genetic constitution of the microorganism involved is 

 evident. This may be related to the findings of Schneider (1949) and 

 Schneider and Zinder (19 56). They showed that diet altered the out- 



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