300 SODIUM 



sodium turnover rates in the dog, about 1 mc Na^" was injected into the 

 jugular vein (Na-8). Food and feces were homogenized in distilled H2O 

 and 2 A^ HNO3, and the calcium removed by oxalate precipitation. Bone 

 was heated in concentrated HNO3 until dissolved, the solution diluted 

 and chilled, the fat removed, and the calcium removed by precipitation 

 with oxalate. Ahquots of these solutions were counted with a dipping 

 Geiger tube, and sodium estimated chemically by use of a flame photom- 

 eter with an internal standard. Plasma and ceUs were diluted and 



measured directly. 



In studies of circulation in human beings, about 200 fxc Na^" has been 

 injected, and external counts made with conventional Geiger tubes 

 (Na-9). ' For determination of sodium space in adults and infants, a 

 dosage of 1 to 1.5 nc Na^^ per kilogram body weight in 1 to 2 ml of a 

 sterile isotonic solution was intravenously injected (Na-10, Na-11). 

 One-millihter samples of serum, urine, and cerebrospinal fluid plus 1 drop 

 of a detergent (Acidolate) were dried at 70°C in metal planchets for count- 

 ing with an end-window tube. Tissue samples were digested in HNO3 

 for solution counting. For chemical analyses, dry-ashing at 540°C was 

 employed, followed by removal of the greater part of calcium and phos- 

 phorus and then reaction with zinc uranyl acetate. The circulation of 

 damaged skin and the circulatory efficiency of tubed pedicles and flaps 

 have been measured by intradermal injection of 0.1 to 3 /xc Na^^ and esti- 

 mation of its removal by a Geiger tube placed over the injection site 

 (Na-12, Na-13). In a long-term study of Na removal in man, 50 to 90 mc 

 Na22 as NaCl in 2 ml HoO was injected intravenously (Na-14). Sixteen 

 free-falhng drops of serum or urine from a cahbrated micropipette was 

 placed on filter-paper disks attached with rubber cement to metal disks 

 for counting with an end-window tube. For measurements of exchange- 

 able Na in man, 50 to 70 mc Na^" was injected intravenously, and fluids 

 assayed directly by hquid counting (Na-15). 



Na-1 Wallace, William M., Malcolm HoUiday, Margaret Cushman, and J. Russell 

 Elkinton: The Application of the Internal Standard Flame Photometer to 

 the Analysis of Biologic Material, J. Lab. Clin. Med., 37: 621-629 (1951). 



Na-2. Zak, Bennie, Robert E. Mosher, and Albert J. Boyle: A Review on Flame 

 Analysis in the Clinical Laboratory, Am. J. Clin. Pathol., 23: 60-77 (1953). 



Na-3 Mosher, Robert E., A. J. Boyle, Edward J. Bird, S. D. Jacobson, Thomas M. 

 Batchelor, Lloyd T. Iseri, and Gordon B. Myers: The Use of Flame Photome- 

 try for the Quantitative Determination of Sodium and Potassium m Plasma 

 and Urine, Am. J. Clin. Pathol., 19: 461-470 (1949). 



Na-4. O'SuUivan, Michael: Rapid Determination of Urinary Sodmm, /. Lab. Chn. 

 il/ed., 41: 959-962 (1953). 



Na-5 Stone, Gilbert C. H., and Joseph W. Goldzieher: A Rapid Colonmetnc 

 Method for the Determination of Sodium in Biological Fluids and Particularly 

 in Serum, J. Biol. Chem., 181: 511-521 (1949). 



