MILAN 



for 4 or 5 days. They still had a 25% elevation in heat production. 

 Is there any explanation for this? I do not understand how dynamic 

 action can last so long. 



EAGAN: Yoshimura, lida and Koishi (1952)* have shown that 

 when the protein fraction in the diet is increased there is an increase 

 in BMR which persists for several days after the protein intake is 

 reduced to normal. This result was obtained by merely doubling the 

 protein intake from a normal 75 grams to 150 grams per day. 



MORRISON: What is the implication of this? Are the amino acids 

 stored away and then used gradually? Would the high protein diet 

 encourage their storage? 



HANNON: There is a very confusing picture with respect to the 

 mechanism of specific dynamic action. We attempted to get at this 

 one time by infusing an animal intravenously with amino acids to 

 see how they affected his metabolism. Nothing happened, so we dis- 

 continued the experiments. 



MORRISON: Nothing happened? Are there not reports in litera- 

 ture showing that infused amino acids give a normal specific dyna- 

 mic action? 



HANNON: This was intravenous infusion where two different 

 amino acids — glycine and glutamate — were tested. Neither caused 

 any increase in the metabolic rate. It is interesting that you do 

 get the specific dynamic action when the animal eats protein. This 

 might suggest that the mechanism of SDA may have something to 

 do with gut absorption; I do not really know. 



ADAMS: This picture on theSDAeffect of glycine is really con- 

 fused. Dr. Carlson tried feeding glycine and noted a subsequent 



*Yoshimura, H., T. lida and H. Koishi, 1952. Studies on the reactivity of skin 

 vessels to extreme cold. Part III. Effects of diets on the reactivity of skin vessels 

 to cold. Jap. J. Physiol . 2:310-315. 



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