scholarly journals Genetic variation and evolution in the red cell carbonic anhydrase isozymes of macaque monkeys

1971 ◽  
Vol 5 (2) ◽  
pp. 183-200 ◽  
Author(s):  
Richard E. Tashian ◽  
Morris Goodman ◽  
Verle E. Headings ◽  
Joseph DeSimone ◽  
Richard H. Ward
1973 ◽  
Vol 158 (1) ◽  
pp. 365-376 ◽  
Author(s):  
Joseph Desimone ◽  
Erik Magid ◽  
Margareta Linde ◽  
Richard E. Tashian

1973 ◽  
Vol 8 (2) ◽  
pp. 157-164 ◽  
Author(s):  
Erik Magid ◽  
Joseph DeSimone ◽  
Richard E. Tashian

1975 ◽  
Vol 38 (4) ◽  
pp. 710-718 ◽  
Author(s):  
R. E. Forster ◽  
E. D. Crandall

A stopped-flow rapid-reaction apparatus was used to follow the time course of extracellular pH in a human red cell suspension following a sudden increase in PCO2. The extracellular pH change was slow (t1/2 similar to 3.5 s) considering the presence of carbonic anhydrase in the cells. When carbonic anhydrase was added to the extracellular fluid, the half-time was reduced to less than 20 ms. The explanation for these phenomena is that the equilibration of H+ across the red cell membrane is rate-limited by the uncatalyzed reaction CO2 plus H2O formed from H2CO3 outside the cells. A theoretical model was developed which successfully reproduced the experimental results. When the model was used to simulate CO2 exchange in vivo, it was determined that blood PCO2 and pH require long times (greater than 50 s) to approach equilibrium between cells and plasma after leaving an exchange capillary. We conclude that cell-plasma equilibrium may never be reached in vivo, and that in vitro measurements of these quantities may not represent their true values at the site of sampling.


1996 ◽  
Vol 271 (4) ◽  
pp. R973-R981 ◽  
Author(s):  
S. Glombitza ◽  
S. Dragon ◽  
M. Berghammer ◽  
M. Pannermayr ◽  
R. Baumann

In late chick embryos, coordinate activation of red cell carbonic anhydrase II (CAII) and 2,3-diphosphoglycerate (2,3-DPG) synthesis is initiated by hypoxia. The effects are mediated by unidentified hormonal effectors resident in chick plasma. In the present investigation, we have analyzed the effect of adenosine receptor stimulation on embryonic red cell CAII and 2,3-DPG synthesis. We find that primitive and definitive embryonic red blood cells from chick have an A2a adenosine receptor. Stimulation of the receptor with metabolically stable adenosine analogues causes a large increase of red cell adenosine 3',5'-cyclic monophosphate (cAMP) and subsequent activation of red cell CAII and 2,3-DPG production in definitive red blood cells and of CAII synthesis in primitive red blood cells. Direct stimulation of adenylyl cyclase with forskolin has the same effect. Analysis of red cell protein pattern after labeling with [35S]methionine shows that stimulation of red cell cAMP levels activates synthesis of several other proteins aside from CAII. Presence of actinomycin D inhibits cAMP-dependent changes of protein synthesis, indicating that cAMP-dependent transcriptional activation is required. In contrast to the stable adenosine receptor analogues, adenosine itself was a very weak agonist, unless its metabolism was significantly inhibited. Thus, besides adenosine, other effectors of the adenylyl cyclase system are likely to be involved in the O2 pressure-dependent regulation of red cell metabolism in late development of avian embryos.


Blood ◽  
1981 ◽  
Vol 57 (2) ◽  
pp. 209-217 ◽  
Author(s):  
L Lenzerini ◽  
U Benatti ◽  
A Morelli ◽  
S Pontremoli ◽  
A De Flora ◽  
...  

Abstract FX is a red cell NADP(H)-binding protein that has been well defined biochemically and immunologically but whose function is still unknown. Preliminary data indicated that the levels of this protein are significantly increased in hemizygotes, heterozygotes, and homozygotes for the G6PD Mediterranean mutant, thus raising the question of whether or not the individual variation in FX levels is more or less directly influenced by X-linked genes. The present study, based on a large series of population and family data collected in Sardinia, confirms unequivocally the above mentioned interaction, but shows at the same time that the variances in FX levels “between sibships” are 2–3 times larger than those “within sibships,” when the analysis is done separately for the G6PD-normal or the G6PD-deficient sibs. From the comparison of the interclass and intraclass correlation coefficients, it appears that about 60% of the total variation of FX is of genetic origin. Moreover, the FX levels of children, analyzed in a pairwise manner, were found to be more positively correlated with those of their fathers (r = 0.39) than with those of their maternal grandfathers (0.20). This latter finding obviously favors the conclusion that “autosomal”; rather than “X-linked” genes are involved in the determination of the FX levels.


1984 ◽  
Vol 429 (1 Biology and C) ◽  
pp. 324-331 ◽  
Author(s):  
SAMUEL H. BOYER ◽  
HARRY OSTRER ◽  
KIRBY D. SMITH ◽  
KEITH E. YOUNG ◽  
ANDREA N. NOYES

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