PHOSPHATES AND THERAPEUTIC AGENTS 



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Findlay et al., 1954; Findlay et al., 1953). Although measurements 

 of oxygen uptake were not made in these experiments concentra- 

 tions of this order are known to be inhibitory and the decreased 

 incorporation of radioactivity probably reflects a decreased rate of 

 synthesis of adenosine triphosphate. Indirect measurements of the 

 rate of synthesis of adenosine triphosphate in slices of cerebral 

 cortex in the presence of barbiturates have been made by Messer 

 (1958). It was found that the synthesis of glutamine (a process 

 known to be dependent upon an adequate supply of adenosine 

 triphosphate) was decreased by a number of barbiturates, but only 

 in direct ratio to the decrease in oxygen uptake (Table 22). 

 Concentrations to produce this effect were some 5-10 times higher 

 than those found to be depressant in vivo. Since similar changes 

 were found when cyanides were added to the system it was 



Table 22, — Effect of Depressants upon the Synthesis of Energy-rich 

 Phosphates in Cerebral Slices and Dispersions of Whole Brain 



Data from Messer (1958); 

 McEwan (1949). 



Case and Mcllwain (1951); and Eiler and 



