CHATONNET, J. 
DISCUSSION 
MR. EAGAN: In your first series of experiments, did your 
metabolism figures at the ambient temperature represent the maxi- 
mum metabolic rate that you measured at that temperature? Was 
this the sum of metabolism? 
DR. CHATONNET: The metabolism figures represent the meta- 
bolic rate actually measured at each ambient temperature. In very 
cold ambient temperature and only after exclusion of muscular 
activity by denervation in an extensive field, the maximum is 
reached. By adrenal demeduUation I try to suppress a thermogen- 
etic factor and, in such a way, to evaluate its importance. Of 
course, the vasomotor effect of adrenal medulla hormones plays 
some role in heat loss, but in the dog which showed beforehand a 
maximum of metabolism in the cold, the increase of heat loss follow- 
ing this operation does not modify this metabolism level. It only 
reduces the range of external temperatures regulated. 
DR. CLARK: Since you apparently kept your animals alive a 
very long time, one wonders about sensitization to circulating 
hormones. Were they more sensitive to adrenalin than normals? 
DR. CHATONNET: Yes, the chronic spinal dog, the acute dog, is 
very sensitive to epinephrine, as far as the vascular action. 
DR. CLARK: I was thinking of action on skin vessels. 
DR. FREEMAN: Doesn't enervation take place after spinal sec- 
tion? 
DR. CLARK: In the cat it does. And how about pitressin? Did 
you try pitressin in any of them? 
DR. CHATONNET: I didnottry it.I do not believe that hypophy- 
sis plays an important role in regulation in spinal dogs, at least in 
the capacity of thermogenesis. 
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