scholarly journals Ionic and osmotic equilibria of human red blood cells treated with nystatin.

1979 ◽  
Vol 74 (2) ◽  
pp. 157-185 ◽  
Author(s):  
J C Freedman ◽  
J F Hoffman

Human red blood cells have been incubated in the presence of nystatin, which allows Na and K, as well as Cl and pH to equilibrate rapidly when cell volume is set with external impermeant sucrose. The intracellular mean ionic activity coefficients, relative to values in the extracellular solution, for KCl and NaCl are 1.01 +/- 0.02 and 0.99 +/- 0.02 (SD, n = 10), respectively, and are independent of external pH, pH o, and of [sucrose]o. With nystatin the dependence of red cell volume on [sucrose]o deviates from ideal osmotic behavior by as much as a factor of three. A virial equation for the osmotic coefficient, phi, of human hemoglobin, Hb, accounts for the cell volumes, and is the same as that which describes Adair's measurements of phi Hb for Hb isolated from sheep and ox bloods. In the presence of nystatin the slope of the acid-base titration curve of the cells is independent of cell volume, implying that the charge on impermeant cellular solutes is independent of Hb concentration at constant pH. By modifying the Jacobs-stewart equations (1947. J. Cell. Comp. Physiol. 30: 79--103) with the osmotic coefficients of Hb and of salts, a nonideal thermodynamic model has been devised which predicts equilibrium Donnan ratios and red cell volume from the composition of the extracellular solution and from certain parameters of the cells. In addition to accounting for the dependence of cell volume on osmotic pressure, the model also describes accurately the dependence of Donnan ratios and cell volumes on pHo either in the presence or absence of nystatin.

1985 ◽  
Vol 248 (3) ◽  
pp. R293-R301 ◽  
Author(s):  
J. P. Hannon ◽  
C. A. Bossone ◽  
W. G. Rodkey

When estimated by the dilution of 51Cr-labeled red blood cells under nearly basal conditions, immature splenectomized pigs (n = 20) had a circulating red cell volume of 17.8 +/- 1.64 (SD) ml/kg. At an assumed body-to-large vessel hematocrit (BH:LH) ratio of 0.9, plasma volume was 49.6 +/- 3.12 ml/kg and blood volume 67.3 +/- 3.67 ml/kg. Sham-operated pigs (n = 20) had a circulating red cell volume of 16.2 +/- 1.39 ml/kg, a plasma volume of 51.1 +/- 3.42 ml/kg, and blood volume of 67.2 +/- 4.12 ml/kg. Kinetic analysis of early 51Cr loss from the circulating blood of the sham-operated pigs indicated a splenic red cell sequestration of 4.5 +/- 0.89 ml/kg and a t1/2 of 9.76 +/- 1.93 min for splenic red cell turnover. Epinephrine injection (n = 6) and physical restraint (n = 8) caused rapid mobilization of splenic red blood cells in sham-operated pigs. Volume estimates in splenectomized pigs (n = 7) based on simultaneous dilutions of 51Cr-labeled red blood cells and 125I-labeled bovine albumin gave circulating red cell, plasma, and blood volumes of 18.4 +/- 2.46, 60.7 +/- 4.01, and 79.0 +/- 3.51 ml/kg, respectively, and a BH:LH ratio of 0.756 +/- 0.029. The latter value may have reflected an overestimation of plasma volume by the 125I-labeled albumin procedure.


1961 ◽  
Vol 200 (3) ◽  
pp. 614-618 ◽  
Author(s):  
J. J. Friedman

The distribution of radioiodinated plasma and radioiron-labeled red blood cells between the liver, intestine and spleen were determined during the induction and development of tourniquet shock in mice. The data obtained indicate that plasma and red blood cells are distributed differentially throughout the splanchnic vasculature such that plasma volume of liver, intestine and spleen remain depressed for the entire shock interval, as does splenic red cell volume. After an early decline, the red cell volume of liver and intestine become elevated to a level above control. This differential distribution of plasma and red cells in liver and intestine is attributed to alterations in peripherovascular tone and suggests that a venous component becomes prominent late in shock and may act to pool blood out of active circulation.


1957 ◽  
Vol 190 (1) ◽  
pp. 19-24 ◽  
Author(s):  
Joseph F. Garcia

Using the Fe59-labeled cell dilution technique, the blood, plasma and red cell volume and total circulating hemoglobin have been determined on 259 male rats varying in age from 1 to 340 days. An anemic period exists in the male rat which is maximal between 15 and 20 days of age. This anemia is observed in terms of a decrease in the volume of red blood cells per gram of rat as well as in hematocrit and hemoglobin concentration values. However, throughout this anemic period there is a continual increase in total red cell volume and, in fact, the daily gain of red blood cells per gram of rat is greater during this period than at any time thereafter. In spite of the very high rate of erythropoiesis occurring at this time the growth of the body mass as a whole exceeds it and so for a time anemia results.


1978 ◽  
Vol 44 (2) ◽  
pp. 254-257 ◽  
Author(s):  
Y. Kakiuchi ◽  
A. B. DuBois ◽  
D. Gorenberg

Hansen's membrane manometer method for measuring plasma colloid osmotic pressure was used to obtain the osmolality changes of dogs breathing different levels of CO2. Osmotic pressure was converted to osmolality by calibration of the manometer with saline and plasma, using freezing point depression osmometry. The addition of 10 vol% of CO2 to tonometered blood caused about a 2.0 mosmol/kg H2O increase of osmolality, or 1.2% increase of red blood cell volume. The swelling of the red blood cells was probably due to osmosis caused by Cl- exchanged for the HCO3- which was produced rapidly by carbonic anhydrase present in the red blood cells. The change in colloid osmotic pressure accompanying a change in co2 tension was measured on blood obtained from dogs breathing different CO2 mixtures. It was approximately 0.14 mosmol/kg H2O per Torr Pco2. The corresponding change in red cell volume could not be calculated from this because water can exchange between the plasma and tissues.


1968 ◽  
Vol 19 (1) ◽  
pp. 145 ◽  
Author(s):  
PH Springell

Twenty-four steers, comprising British (Herefords and Hereford x Shorthorn crosses), Zebu (Africander), and Zebu cross (British x Brahman or Africander) breeds, were maintained either on pasture or yarded, and fed on diets of a low and a high nutritional value. Blood volumes were determined on five occasions at intervals of 3 months by the 51Cr labelling technique, plasma and red cell volumes being then derived from the venous haematocrit. The blood plasma, and red cell volumes are all very significantly, correlated with, and represent respectively 4.97, 3.27, and 1.70% of, the fasting body weight. To avoid the confounding effect of body weight, the parameters are expressed as "contents", i.e, in terms of volume per kilogram fasting body weight. In the grazing group breed differences were generally absent. This may in part be due to the fact that the Zebu crossbreds belonged mostly to the F2 and partly to the F3 generation. In the yarded group, where F1 crossbreds were compared with British steers, breed differences were more frequent. British steers tended to have higher plasma contents, but lower red cell contents and haematocrits. Nutrition had no effect on plasma contents, but good nutrition was generally associated with higher haematocrits, as well as with elevated blood and red cell contents. Seasonal differences were in evidence, and all parameters generally reached minimal values in winter or spring. The significance of these findings in relation to adaptation to a tropical environment is discussed. The haematocrit does not necessarily reflect changes in the red cell volume. There is also some indication that the water and plasma contents may be related. The possible usefulness of the red cell volume for predicting the body composition is discussed.


1985 ◽  
Vol 249 (1) ◽  
pp. C124-C128 ◽  
Author(s):  
P. K. Lauf ◽  
C. M. Perkins ◽  
N. C. Adragna

The effects of incubation in anisosmotic media and of metabolic depletion on ouabain-resistant (OR) Cl--dependent K+ influxes stimulated by N-ethylmaleimide (NEM) were studied in human red blood cells using Rb+ as K+ analogue. The NEM-stimulated but not the basal Rb+-Cl- influx measured in phosphate-buffered anisosmotic media was found to be cell volume dependent. When cellular ATP, [ATP]c, was lowered to less than 0.10 of its initial level by exposure to nonmetabolizable 2-deoxy-D-glucose, the NEM-stimulated but not the basal Cl--dependent Rb+ influxes were abolished. Metabolically depleted red blood cells subsequently repleted by incubation in glucose plus inosine regained the NEM-inducible Rb+ (K+) transport activity. The difference in the time course of ATP breakdown and Rb+ influx inhibition suggests that energization of the NEM-stimulated Rb+ flux by metabolism may involve factors additional to ATP.


1980 ◽  
Vol 8 (3) ◽  
pp. 356-358 ◽  
Author(s):  
N. S. Agar ◽  
G. B. H. Lewis

No significant changes were found in packed cell volume, haemoglobin concentration and red cell glutathione levels in patients before and after anaesthesia with halothane or enflurane. These results, though unable to explain the mechanism, support the earlier suggestion that glutathione plays little, if any, role in protecting liver against toxic effects of these anaesthetic agents or their metabolites.


2002 ◽  
Vol 9 (8) ◽  
pp. 878-885 ◽  
Author(s):  
Hilde Kanli Galtung ◽  
Vibeke Sørlundsengen ◽  
Kjell S. Sakariassen ◽  
Haakon B. Benestad

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