VIRULENCE AND BACTERIAL INFECTION 



Corti- Corti- 



Days Post 50ug sone 6 70ug sone 6 Cortisone 

 Injection LPS 50ug LPS LPS 70ug LPS Controls 



Table VII. Hormonal protection against Lipopolysaccharide. Treatment and sur- 

 vivors. 



With this in mind, five mg of cortisone acetate was administered 

 subcutaneous ly immediately before intraperitoneal injection of 50 

 Aig of lipopolysaccharide (endotoxin). When the animals were main- 

 tained at 5° C post- injection survivorship was slightly but not sig- 

 nificantly greater (P>0.05) in hormone treated mice than in animals 

 not receiving hormone (88.5 per cent vs. 63,3 per cent, Table VII). 

 However, with a larger quantity of lipopolysaccharide, the protection 

 afforded by cortisonewas clearly demonstrated. When an LD^qq dose 

 (70 /Li g) of lipopolysaccharide was given to mice exposed to 5° C after 

 injection, all 40 controls died, while 24 of 30 mice given 5 mg of 

 cortisone acetate survived (P<0.001). Cortisone alone killed no ani- 

 mals. 



Adrenocorticotrophic Hormone 



Exogenous ACTH administration has been reported to sensitize 

 mice to the lethal effects of endotoxin. This occurs presumably be- 

 cause glycocorticoids are released too promptly in animals that 

 receive both endotoxin and ACTH (Berry and Smythe, 1959; 1961) 

 to fulfill the protective action the corticoids normally afford against 

 endotoxin poisoning alone. The experiments described below were 

 carried out to determine whether or not cold exposed animals would 

 be further sensitized to lipopolysaccharide if given ACTH. The re- 



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