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FACTORS INFLUENCING THE RESPIRATION OF ERYTHROCYTES II. MAMMALIANRETICULOCYTES BY G. PAYLING WRIGHT (From the Cancer Commission of Harvard University, and the Department of Physical Chemistry in the Laboratories of Physiology, Harvard Medical School, Boston) (Accepted for publication, July 28, 1930) Cohnstein and Zuntz (1) were the earliest investigators who clearly pointed out that certain types of blood exhibit a metabolism involving the disappearance of oxygen and reduction of the hemoglobin
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  FACTORS INFLUENCING THE RESPIRATION OFERYTHROCYTESII. MAMMALIAN RETICULOCYTESBY G. PAYLING WRIGHT (From the Cancer Commission of Harvard University, and the Department of PhysicalChemistry in the Laboratories of Physiology, Harvard Medical School, Boston) (Accepted for publication, July 28, 1930)Cohnstein and Zuntz (1) were the earliest investigators who clearlypointed out that certain types of blood exhibit a metabolism involvingthe disappearance of oxygen and reduction of the hemoglobin. Thismetabolism was most evident in fetal blood, which, they observed,gradually darkened in color upon standing and upon evacuation lib-erated less oxygen than before. They ascribed this loss of oxygen tothe action of the red cells, many of which, at the stage of developmentof the blood which they examined, still possessed large vesicular nuclei.Since then the metabolism of the blood has been very activelystudied, notably by Warburg, by Morawitz, and by Harrop. Therather extensive literature has been well reviewed by Morawitz (2).In general, it may be summarized by stating that it is now agreed thatthe normal orthochromatic erythrocytes, which form the vast majorityof the circulating red cells of mammals, have a negligible if anyrespiration (Daland and Isaacs (3)). On the other hand the poly-chromatic cells, which have been recently liberated from the bonemarrow and which are found in large numbers in young animals andduring active blood regeneration, exhibit an easily measurableconsumption of oxygen and formation of carbon dioxide. The earliernucleated cells, ordinarily present only in the bone marrow in mam-mals, and the nucleated circulating erythrocytes of birds and amphibia,also respire very actively.With the exception of Warburg's studies (4), which were largelyconcerned with the manner in which respiration was inhibited by201 The Journal of General Physiology    onA  u g u s  t  2  5  ,2  0  0 4 www. j   g p. or  gD  ownl   o a d  e d f  r  om   202 RESPIRATION OF ERYTI-IROCYTES. II various narcotics, the factors which influence this metabolism havenot been extensively investigated. This paper deals with the varia-tions in the respiration of the reticulocytes of the rabbit brought aboutby various alterations in the medium in which they are suspended. Methods The majority of the methods used in this investigation have already beendescribed in the previous paper. The blood used was obtained from the ear veinand was defibrinated as it was collected by shaking with glass beads. Before se it was filtered through cotton wool to remove the coagulated fibrin and with it the large majority of leucocytes (Warburg (5)).The rabbits were made anemic by intraperitoneal injections of phenylhydrazinehydrochloride (15 rag. per kilo) dissolved in normal physiologicalsaline solution.The anemia reached its greatest severity in about 7 days. The blood used inthese experiments was removed from animals at a time when there was a largeproportion of reticulocytes and consequently a high rate of respiration. The Respiration of the Blood during the Onset and Recovery Stages inPhenylhydrazine Anemia An injection of phenylhydrazine into a rabbit is rapidly followed bythe development of anemia. With suitable quantities of the sub-stance (15 to 20 rag. per kilo) the red cell count may be caused to fallfrom its normal value of rather over five million to between one andtwo million red cells per c. mm. Regeneration, however, sets in veryquickly, and by the time that the anemia has become most severe,between the sixth and eighth days, the blood may contain enormousnumbers of reticulocytes. When the red cell count falls below twomillion per c. mm., more than 50 per cent of the cells may be reticulo-cytes, or more than one million per c. mm. More commonly thenumber lies between six and eight hundred thousand per e.mm. Ifthe oxygen consumption of such a specimen of blood be determined itwill be found to have a very much higher value than that from a normalrabbit. Harrop (6) has shown that a rough proportionality existsbetween the number of reticulocytes in, and the oxygen consumptionof, various pathological human bloods. Similarly Derra (7) studiedthe oxygen consumptions of blood during the remissions resulting fromthe administration of liver extract in patients suffering from perniciousanemia. He found a similar relationship, though not so close as that  onA  u g u s  t  2  5  ,2  0  0 4 www. j   g p. or  gD  ownl   o a d  e d f  r  om   G. PAYLING WRIGHT 203observed by Harrop, between the oxygen consumption and the reticu-locyte content of the blood at various times in the remissions.In the following experiment two rabbits were made anemic byinjection with phenylhydrazine. Red cell counts, reticulocyte countsand oxygen consumption determinations were made every second dayuntil the main wave of liberation of reticulocytes had subsided. Theobservations are to be found in Table I and Fig. 1. TABLE I The Oxygen Consu~nption of Reticulocytes at Various Phases in ~he Anemia Inducedby the Injection of Phenylhydrazine Rabbit No. 28 40 Day:ensurned Per billion reties. per hour before inject. 63.01st after inject. 57.83rd 64.2 5th 64.77th 65.59th 54.3llth 59.913th 55.3before inject. 53.61st after inject. 59.73rd 47.65th 63.27th 55.99th 52.8llth 52.413th 56.7 From Table I it can be seen that the actual number of reticulo-cytes per c.mm. of blood increased, in one animal to more than nine,in the other to more than six, times their initial figures, and that theoxygen consumption of the blood underwent a concurrent change.But in spite of the very large alteration in both, the oxygen consump-tion for every billion (thousand million) reticulocytes was, withinreasonably close limits, the same throughout the course of theexperiment.  onA  u g u s  t  2  5  ,2  0  0 4 www. j   g p. or  gD  ownl   o a d  e d f  r  om   204 RESPIRATION OF ERYTtIROCYTES. II There are at least two possible explanations for this rather strikinglyuniform relationship between oxygen consumption and reticulocyteconcentration. In the first place it is possible that the reticulum in thecell either promotes oxidation or is itself oxidized at the same rate atall stages in its gradual disappearance. When taken in conjunctionwith the cytological appearances of the reticulocytes with their veryvariable content of basophil filaments, such an assumption seems IA 7C to so |a*i~ U = | (~z IO I DAYS AFTER INJECTION FzG. 1. Showing the oxygen consumption of reticulocytes related to theirconcentration in the blood at various stages of an anemia produced by phenyl-hydrazine. hardly probable. A second and seemingly more likely explanation isthat the reticulocyte stage of development is of comparatively shortduration in comparison with the whole duration of the wave of reticulo-cyte production evoked by the phenylhydrazine. Under thesecircumstances the oxygen consumption curve for the blood wouldrepresent, at any one particular time, the summation of the oxygenconsumption of reticulocytes at all stages in their life history. In this  onA  u g u s  t  2  5  ,2  0  0 4 www. j   g p. or  gD  ownl   o a d  e d f  r  om 
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