Estimation of nucleotide content of red cells.

This paper describes a method of estimating the nucleotides in red blood cells. The technique used is based on that of Cohn and Carter (1950), who have shown that the nucleotides, adenosinemonophosphate (A.M.P.), adenosinediphosphate (A.D.P.), and adenosinetriphosphate (A.T.P.) can be separated by an anion exchange column. Bartlett, Savage, Hughes, and Marlow (1953) have successfully used this method for estimations on 100 ml. of whole blood; however, this volume is inconveniently large, especially if serial estimates are to be carried out. The present method uses only 1 ml. of red cells. Quantitative measurements have been made using the characteristic ultra-violet light absorption of adenine. In order to reduce the quantity of other substances also absorbing ultra-violet light, preliminary precipitation of the nucleotides as barium salts is carried out before placing them on the column. After elution of the nucleotides in separate fractions, the ultra-violet light absorption at three wavelengths is measured and correction for impurities made by the method of Morton and Stubbs (1946). This paper contains a detailed account of the method and findings of the nucleotide content of fresh red cells from 12 normal subjects. In order to demonstrate the use of the method, the results obtained before and after incubating stored red cells with adenosine are described.