Inhibition of Reticulocyte Lysis by Alkyl Polyamines

Abstract

phopyridine nucleotides have been studied in rat liver after fasting and during oxidation of ethanol. The changes in diphosphopyridine nucleotides have also been studied in baker's yeast during ethanol oxidation. By fasting alone a slight decrease of DPN/DPNH ratio mainly due to a fall in the concentration of DPN is noted. Total DPN + DPNH is also decreased slightly. n'hen the animals are metabolizing ethanol the DPN,'DPNH ratio decreases further, due to an increase of DPNH, and especially in the fasted animals a fairly marked increase of the total DPN + DPNH can be noted. Similar changes are observed in baker's yeast during ethanol oxidation. Triphosphopyridine nucleotide is mainly present in the liver in its reduced form, and the TJ'N/TIWH does not. change significantly during ethanol oxidation. Inhibition of Reticulocyte Lysis by AlkylPolyamines. (27375) J. R. LITTLE (Introduced by G. Brecher) Hematology Scrvice, c'lin. Path. Dept., Clinii.cal Cenlrr, .V.I.II., P.H.S., Hethesda, M d .The participation of the alkyl polyamines in many diverse biological and biochemical phenomena has made this class of organic compounds a source of increasing interest. Spermine, spermidine and related substances are widely distributed in animal tissues and microorganisms ; yet specific information about their function(s) is lacking. A variety of biological effects has been demonstrated in selected systems ( 1 ) including: 1 ) promotion of growth of microorganisms, 2 ) stabilization of bacteria, bacterial protoplasts, mitochondria, ribosomes, bacteriophages, and transforming principle, 3) binding to nucleic acids, heparin, and certain lipids, and 4) stabilization of enzyme activity.This report deals with the stabilizing effect of spermine and related polyamines on the reticulocyte undergoing spontaneous lysis.Methods. Blood samples, anticoagulated with dry dipotassium versenate, were obtained from human subjects and Sprague-Dawley rats. Reticulocyte-rich blood was obtained from female Sprague-Dawley rats weighing 150-200 g, previously given subcutaneous injections of phenylhydrazine hydrochloride( 2). Reticulocyte counts of up to SO: %, were obtained. Reticulocyte counts were made on all blood samples using the methods of Brecher (3,4).Dilute suspensions of red blood cells and reticulocytes were incubated in phosphate buffered saline following the osmotic fragility method of Dacie ( 5 ) . For each blood sample tested, a duplicate series of tubes was used containing 2 ml aliquots of serial dilutions of 0.150 hl NaCl in 0.01 M sodium phosphate buffer at pH 7.40. To one series of tubes 0.01 ml of an alkyl amine solution was added so that the final concentration of amine was 0.5 mM. A second series of tubes without alkyl amine served as a control. Whole blood (0.02 ml) was then delivered into each tube and mixed immediately by gentle inversion. Tubes were incubated at room temperature ( 23"-2SoC) for 30 minutes and then centrifuged at 2000 rpm for 5 minutes. The amount of hemolysis (referred to as immediate hemolysis) was determined b...