103 



BARRON: No, because we did the same experiment during the war and 

 found respiration inhibited 4 hours afterwards. 



SPIEGELMAN: It isn't like a needle where you stick it in and pull it 

 out. That is my point. 



BARRON: I think it is. 



PATT: How do you interpret Altman's findings of an increase in respi- 

 ration of rat marrow homogenates immediately after irradiation. 



BARRON: We found the same thing. 



In single cell irradiations, whether there is an increase or a decrease 

 depends on whether the action is on the glutathione content of the cell, which 

 serves to inhibit respiration, or on the cellular enzymes. We showed with 

 both sea urchin egg and sea urchin sperm that a small dose of X-rays could in- 

 crease respiration. With fertilized sea urchin eggs, I think we could get an in- 

 crease with 100 r; with unfertilized eggs 200 r were required; and with sperm 

 100 r. 



PATT: I am referring now to mammalian tissue. I think that Altman 

 found that there was first an immediate increase in respiration and then a de- 

 crease on the next day after an exposure to several hundred roentgens. I offered 

 Altman's work only in response to the inference that the decrease in respiration 

 at 4 hours would probably also be observed immediately after exposure. 



spleen. 



marrow. 



BARRON: That was not on spleen. 



PATT: No, it was marrow which should probably react similarly to 



BARRON: No, because we were unable to find any inhibition with 



MAZIA: This is an important question. Someone ought to set up the 

 experiment in such a way that the bone marrow respiration could be measured 

 immediately or even during the irradiation. 



CARTER: We did this with bone marrow at one time and found that im- 

 mediately following large amounts of irradiation there is no change in the respi- 

 ration of bone marrow. That is, just immediately afterwards. 



BARRON: We found the same thing. We found inhibition in bacteria 

 immediately after irradiation with exposures as low as 500 r. This was done by 

 irradiating the bacteria in their own culture medium. 



POTTER: It seems to me that the experiments on enzymes and carbo- 

 hydrate metabolism will, in the end, be found to be intimately related to nucleic 

 acid synthesis, and it is to our advantage to try to bring these together and to try 

 to find a common denominator. For instance, in the case of the fluoroacetate 

 phenomenon, I think this is the result of whether the tissue can still activate ace- 

 tate. We are carrying out studies that suggest that whether you can activate ace- 

 tate is a sort of barometer of the ATP-ADP ratio. This is something that you 

 cannot get at experimentally by any direct measurement because of its highly dy- 

 nannic nature, but by indirect experiments, we have a number of indications that 

 the capacity to activate acetate is a baronneter of that ratio. So that I think that 



