SPECIFIC AND NONSPECIFIC RESISTANCE 



lieve Herrington^ wrote which showed that the metabolic rates 

 of mice increase linearily as the ambient temperature decreases. 

 We feel that under these conditions, the "thermostat" has now 

 been set at a new higher level in an attempt at maintenance of 

 homeostatic conditions. 



PREVITE: This animal, being a homeotherm, would maintain 

 a constant body temperature regardless of the environmental 

 temperature as long as it was able to, 



TRAPANI: I am curious about one thing: Is the life span of 

 the mouse, or any other animal for that matter, the same under 

 these conditions of cold exposure as compared to the room tem- 

 peratures ? Our time relationships should be weighed if the life 

 span is different. 



MARCUS: I don't know what the life span of the mouse is if 

 you put him in the cold. 



PREVITE: Barnett and his group"^ have done work on this. 

 They report that mice may be successfully reared in the cold. 

 However, mice reared in the cold survive longer without nesting 

 material than those transferred from a warm room and also 

 deprived of cold. Selye has shown extensive damage to critical 

 organs can result from exposure of rats to cold. 



MARCUS: Well, with these experiments that have gone up to 

 three months involving animals in cold, you have discussed some 

 of the modest changes that occur, at least they seem modest 

 to me, in the periphery of the animal, and I am not aware of any 

 gross changes that occur, any gross pathology that occurs in the 

 animals that are autopsied which could be ascribed to cold alone. 

 With regard to what you said, though, a moment ago, about the 

 mouse being a homeothermic animal and you would expect it to 

 maintain its temperature once it is stabilized at a fairly con- 



2 Am. J. Physiol. 129: L23. 1940. 



3 Barnett et al. 1959. Quart. J. Exp. Physiol. XLIV. 



4 Selye, H. 1943. Kev. Canad. Biol. 2. 



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