Studies on avian erythrocyte metabolism. XIV. Effect of CO2 and pH on P50 in the chicken

1986 ◽  
Vol 250 (2) ◽  
pp. R260-R266 ◽  
Author(s):  
R. Isaacks ◽  
P. Goldman ◽  
C. Kim
Keyword(s):  
Significant Role ◽  
Specific Effect ◽  
Co2 Concentration ◽  
Cell Suspensions ◽  
Bohr Effect ◽  
Chick Embryos ◽  
Adult Chicken ◽  
Avian Erythrocyte ◽  
Erythrocyte Metabolism ◽  
Chicken Blood

The O2 affinity (P50) of erythrocyte suspensions from 18-day chick embryos, from 2-, 5-, 8-, and 14-day chicks, and from mature chickens decreased with increasing concentrations of either CO2 or H+, particularly at a pH near 7.4 and at 37 degrees C. A greater effect on delta P50's was observed from increasing H+ concentration from pH 8.0 to 6.8 in cell suspensions from 18-day embryos (28.8 Torr at 0% CO2) and adult chickens (55.1 Torr at 0% CO2) than from increases in CO2 concentration at any given pH. The Bohr effect (delta log P50/delta pH) in the absence of CO2 was -0.508 and -0.479 for cell suspensions from 18-day chick embryos and adult birds, respectively. The specific effect of CO2 on the Bohr effect, regardless of the CO2 concentration, indicates that the delta P50/0.1 pH is approximately 1.35 and 2.45 Torr for the embryo and adult chicken blood. These results indicate that increasing H+ and CO2 concentrations markedly affect the P50 of chicken blood and that even subtle changes in either could play a significant role physiologically in regulating blood P50 in birds.

scholarly journals Cytological Identification of Proliferating Donor Cells in Chick Embryos injected with Adult Chicken Blood

Nature ◽  
1959 ◽  
Vol 184 (4698) ◽  
pp. 1594-1594 ◽  
Author(s):  
P. M. BIGGS ◽  
L. N. PAYNE
Keyword(s):  
Chick Embryos ◽  
Adult Chicken ◽  
Donor Cells ◽  
Chicken Blood

scholarly journals THE FREQUENCY OF ANTIGEN-SENSITIVE CELLS IN TISSUE TRANSPLANTATION

1969 ◽  
Vol 129 (3) ◽  
pp. 459-467 ◽  
Author(s):  
Norman W. Nisbet ◽  
Morten Simonsen ◽  
Marek Zaleski
Keyword(s):  
Intravenous Injection ◽  
Clonal Selection ◽  
Tissue Transplantation ◽  
Low Doses ◽  
Receptor Specificity ◽  
Adult Chicken ◽  
Single Receptor ◽  
Donor Cells ◽  
Minimum Estimate ◽  
Chicken Blood

Graft-vs.-host (GVH) reactions were performed in chicken embryos by intravenous injection of adult chicken blood dilutions, and the result was scored by weighing the spleens as well as by karyological identification of host and donor metaphases. From the frequency of detectable signs of GVH reaction when low doses of donor cells were injected into hosts containing one foreign allele of the B locus it is concluded that 1–2% must be a minimum estimate for the frequency of antigen-sensitive cells of a given specificity in this system. It is not found possible to reconcile the findings with the strictest form of clonal selection which postulates a single receptor specificity per clone of antigen-sensitive cells.

Studies on avian erythrocyte metabolism

1987 ◽  
Vol 257 (1) ◽  
pp. 177-185 ◽  
Author(s):  
R.E. Isaacks ◽  
L.L. Lai ◽  
P.H. Goldman ◽  
C.Y. Kim
Keyword(s):  
Avian Erythrocyte ◽  
Erythrocyte Metabolism

Influence of carbon monoxide on hemoglobin-oxygen binding

1976 ◽  
Vol 41 (6) ◽  
pp. 893-899 ◽  
Author(s):  
M. P. Hlastala ◽  
H. P. McKenna ◽  
R. L. Franada ◽  
J. C. Detter
Keyword(s):  
Carbon Monoxide ◽  
Oxygen Affinity ◽  
Co2 Concentration ◽  
Bohr Effect ◽  
Oxygen Binding ◽  
Dissociation Curve ◽  
Low Oxygen ◽  
Oxygen Dissociation ◽  
Initial Binding ◽  
Fixed Acid

The oxygen dissociation curve and Bohr effect were measured in normal whole blood as a function of carboxyhemoglobin concentration [HbCO]. pH was changed by varying CO2 concentration (CO2 Bohr effect) or by addition of isotonic NaOH or HCl at constant PCO2 (fixed acid Bohr effect). As [HbCO] varied through the range of 2, 25, 50, and 75%, P50 was 26.3, 18.0, 11.6, and 6.5 mmHg, respectively. CO2 Bohr effect was highest at low oxygen saturations. This effect did not change as [HbCO] was increased. However, as [HbCO] was increased from 2 to 75%, the fixed acid Bohr factor increased in magnitude from -0.20 to -0.80 at very low oxygen saturations. The effect of molecular CO2 binding (carbamino) on oxygen affinity was eliminated at high [HbCO]. These results are consistent with the initial binding of O2 or CO to thealpha-chain of hemoglobin. The results also suggest that heme-heme interaction is different for oxygen than for carbon monoxide.

Studies on avian erythrocyte metabolism

1980 ◽  
Vol 75 (2) ◽  
pp. 485-491 ◽  
Author(s):  
R.E. Isaacks ◽  
C.Y. Kim ◽  
T.J. Legato ◽  
A.E. Johnson ◽  
P.H. Goldman ◽  
...  
Keyword(s):  
Avian Erythrocyte ◽  
Erythrocyte Metabolism

Oxygen-linked CO2 transport in sheep blood

1975 ◽  
Vol 229 (2) ◽  
pp. 334-339 ◽  
Author(s):  
R Bauman ◽  
C Bauer ◽  
EA Haller
Keyword(s):  
Whole Blood ◽  
Oxygen Affinity ◽  
Hemoglobin Concentration ◽  
Cell Suspensions ◽  
Bohr Effect ◽  
Carbon Dioxide Exchange ◽  
Red Cell ◽  
Sheep Blood ◽  
Sheep Hemoglobin ◽  
Binding Curves

We have analyzed oxygen-linked carbamate formation in sheep hemoglobin B by measuring a) the effect of CO2 on oxygen affinity and Bohr effect in red cell suspensions and dilute (1.3 mM Hb4) and concentrated (5 mM Hb4) hemoglobin solutions at 37 degrees C and b) CO2 binding curves of deoxygenated and oxygenated whole blood and hemoglobin solutions, respectively, at the same temperature. In the presence of CO2 both the Bohr effect and oxygen affinity were significantly lower in 1.3-mM Hb4 solutions than in either red cell suspensions or 5-mM Hb4 solutions, while in the absence of CO2 Bohr effect and oxygen affinity did not differ significantly in those preparations. Likewise, the fraction of oxygen-linked carbamate obtained from CO2 binding curves was found to be higher in 1.3-mM Hb4 (0.156 M HbCO2/M HbO2) solutions than in 5-mM Hb4 solutions (0.12 M HbCO2/M HbO2) at pH 7.2. We conclude that hemoglobin concentration affects formation of oxygen-linked carbamate. Total oxygen-linked CO2 in sheep whole blood amounted to 0.18 M CO2/M O2 of which 70% is oxygen-linked carbamate. Assuming a respiratory quotient of 0.85, the contribution of oxygen-linked CO2 to carbon dioxide exchange in sheep blood was computed to be 21%.

scholarly journals Effects of Lithium on Different Membrane Components of Crayfish Stretch Receptor Neurons

1968 ◽  
Vol 51 (5) ◽  
pp. 635-654 ◽  
Author(s):  
Shosaku Obara ◽  
Harry Grundfest
Keyword(s):  
Significant Role ◽  
Specific Effect ◽  
Stretch Receptor ◽  
Receptor Neuron ◽  
Generator Potential ◽  
Crayfish Stretch Receptor ◽  
Soma Membrane ◽  
Receptor Neurons ◽  
Membrane Components

Unlike several other varieties of input membrane, that of the crayfish stretch receptor develops a generator potential in response to stretch when all the Na of the medium is replaced with Li. However, Li depolarizes the receptor neuron, the soma membrane becoming more depolarized than that of the axon. During exposure to Li the cell usually fires spontaneously for a period, and when it becomes quiescent spike electrogenesis fails in the soma but persists in the axon. These effects are seen in the rapidly adapting as well as the slowly adapting cells. The block of spike electrogenesis of the soma membrane is only partly due to the Li-induced depolarization and a significant role must be ascribed to a specific effect of Li.

scholarly journals Studies on Avian Erythrocyte Metabolism. XIII. Changing Organic Phosphate Composition in Age-Dependent Density Populations of Chicken Erythrocytes

1983 ◽  
Vol 62 (8) ◽  
pp. 1639-1646 ◽  
Author(s):  
RUSSELL ISAACKS ◽  
CHANG KIM ◽  
HIA LIANG LIU ◽  
PHYLLIS GOLDMAN ◽  
ALBERT JOHNSON ◽  
...  
Keyword(s):  
Organic Phosphate ◽  
Age Dependent ◽  
Avian Erythrocyte ◽  
Erythrocyte Metabolism ◽  
Chicken Erythrocytes ◽  
Dependent Density
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