CHATONNET, J. 
DR. CHATONNET: I had no results of hypophysectomy. 
DR. HANNON: Have you ever studied what I prefer to call non- 
shivering thermogenesis rather than thermochemical thermogen- 
esis? Have you ever studiedthis in climatized animals or acclimated 
animals? 
DR. CHATONNET: No. 
DR. HANNON: This mi^t prove interesting since these animals 
have almost completely replaced the shivering thermogenesis with 
the non-shivering thermogenesis. 
DR. CHATONNET: In my experiments, dogs are kept at constant 
room temperature of 25 C, except for cold tests. In these conditions 
the non-shivering thermogenesis is not very important. And it is 
doubtful that this mechanism can develop by acclimation in such 
large animals. 
DR. HANNON: I would like to toss out one other question to Dr. 
Chatonnet or any of the other participants here. In these cold clima- 
tized animals, during the processof climatization,they at first have 
a shivering thermogenesis when they go into the cold. This declines 
gradually and reaches minimum values after a few weeks. Concomi- 
tant with this decline, non-shivering thermogenesis increases and 
replaces it. Now if you take this animal out of the cold, his thermo- 
genesis generally drops down to about what a control animal would 
be — a little higher, maybe, with essentially the same as a cold 
animal. You put him back in the cold and almost immediately he 
starts this non-shivering thermogenesis. What is the mechanism? 
MR. EAGAN: It is indeed a mystery, because curarized animals 
and animals that are adrenal demedullated still control this in- 
creased potential for cold- induced thermogenesis. 
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