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



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 I: GUINEA PIG LIVER AND RABBIT KIDNEY CORTEX 



Values in parentheses are ranges, estimate "c" of the 95% range (of Introduction). 



III Medium containing (155-X) mEq Na+, XmEq K+, 4.6 mEq Ca++ and 3.0 mEq Mg++, buffered by 20 raM 

 phosphate; pH = 7.15; addition of glucose, pyruvate, glutamate and furaarate as substrates (5 raM each). 

 IZl Estimated by Warburg's direct method at 37.5°C. /3/ Calculated from final wet weight and final dry weight of 

 slices (dried in oven at IO5OC until constant weight reached.) /4/ Calculated from change in wet weight per unit of 

 tissue solids (dry weight), the wet weight/dry weight ratio of liver tissue or kidney cortex, removed immediately 

 after death, being the reference base of the data. Per cent water content; fresh guinea pig liver, 73.65(71.1-76.6); 

 rabbit kidney cortex. 76.8(73.6-78.6). /5/ Relative tissue volume in vivo = 1.0. 



Contributor: Aebi, H. 



References : [l] Aebi, H., Helvet. physiol. pharm. acta jjO:184, 1952. 

 Helvet. physiol. pharm. acta n^:96, 1953. 



[2] Aebi. H., unpublished. [3] Aebi, H., 



Part II: RABBIT KIDNEY CORTEX, VARIOUS TEMPERATURES 



/I/ Medium for Columns B, C and D containing (155-X) mEq. Na+, X mEq K*, 4.6 mEq Ca''"'' and 3.0 mEq Mg++. 

 buffered by 20 mM phosphate; pH = 7.15; addition of glucose, pyruvate, glutamate and fumarate as substrates (5 mM 

 each). Medium for E and F containing (150-X) mEq Na+, X mEq K+ and 1.4 mEq Ca++, buffered by 3.7 mM 

 phosphate; pH = 7.4; addition of 0.01 M Na-acetate as substrate. HI Calculated from final wet weight and final dry 

 weight of slices (dried in oven at 105°C until constant weight reached). /3/ Estimated by Warburg's direct method. 

 /4/ Original data were given on an initial wet weight basis and have been converted to a dry weight basis. /5/ Calcu- 

 lated as described in Footnote 2, but using different drying technique (dried in a vacuum oven over phosphorus 

 pentoxide at 8OOC). 



Contributor : Aebi. H. 



Reference : [ l] Aebi, 

 1951. 



H., Helvet. physiol. pharm. acta U^-'^'"' 1953. [2] Mudge, G. H., Am. J. Physiol. 165:113, 



308 



