153. EFFECT OF POTASSIUM ION CONCENTRATION ON O^ CONSUMPTION: ANIMAL TISSUES (Continued) 



Values for oxidation quotient (QO2) are expressed in cu mm oxygen per mg final dry weight of tissue per hour, unless 

 otherwise indicated. Media are described in the appropriate footnotes in terms of quantity of ion per liter of solution. 



Part UI: RAT DIAPHRAGM, VARIOUS pH LEVELS 



HI Medium containing (0.120-X) M NaCl, XM KCl, 0.0006 M 



CaClz, 0.0005 M MgCl2. 0.03 M phosphate buffer, and 0.01 M 



pyruvate, except in Lines 15 and 16. HI Plus 0.01 M pyruvate. 



/3/ Plus 0.01 M glucose. 



Contributor : Fitzgerald, L. R. 



Reference : Frunder, H., Zschr. physiol. Chem. 29J_:217, 1953. 



Part IV: RAT BRAIN, VARIOUS SUBSTRATES 



/I/ Initial ionic composition of medium: 120 mEq Na+, 2.4 mEq K+, 3.4 mEq Ca**, 1.6 mEq Mg++; buffered by 

 18 mM/L phosphate, pH = 7.4; concentration of added substrates, 11 mM/L. Additional amounts of potassium (as 

 solid KCl) were added only after first incubation period (30 min). Values in Columns C, E and G are corresponding 

 mean values for the 30-min period following addition of KCl. /2/ Estimated by Warburg's direct method at 37.5°C. 



Contributor : Aebi, H. 



Reference: Dickens, F., and Greville, G. D., Biochem. J., Lond. 29:1468, 1935. 



Part V: RAT CEREBRAL CORTEX, VARIOUS SUBSTRATES 

 Medium: Krebs-Ringer solution with Ca++ reduced to 4.5 x 10-4 M, pH 



7.4. 



/I/ All substrates present in 0.01 M quantities. 



Contributor : Fitzgerald, L. R. 



Reference : Lipsett, M. N., and Crescitelli, F., Arch. Biochem. and Biophys. 28:329, 1950. 



309 



