Blood viscosity during the neonatal period: The role of plasma and red blood cell type

Abstract To clarify the molecular abnormality of pyruvate kinase (PK) deficiency identified in the mutant mice of CBA-Pk-1slc/Pk-1slc, we cloned murine red blood cell-type PK (R-PK) cDNA of those animals. The cDNA sequence spans 1827 bp, including an open reading frame that can encode 574 amino acids. Homology in the coding sequences between murine and human R-PK was 86.1% at nucleotide and 91.5% at amino acid levels. A homozygous missense mutation at nucleotide 1013 GGT-->GAT was identified in the cDNA sequence of the mutant, causing a single amino acid substitution at no. 338Gly-->Asp of the murine R-PK. Six amino acid residues, 335Val-336Ala-337Arg-338Gly-339Asp-340L eu, were encoded in exon 8 of both human and rat L (liver-type)/R-PK genes and were evolutionarily conserved in PK from bacteria through humans. 337Arg was reported to be important for substrate binding, suggesting that the amino acid change would impair substrate affinity of the PK subunit. A homozygous missense mutation at the catalytic domain has been identified in a human PK variant, PK Hong Kong (941ATT-->ACT, 314 Ile-- >Thr). Although both 1013A and 941C gave rise to an amino acid change adjacent to the active site and may interfere with substrate binding to the subunit, the degree of anemia was much more severe in the human case. The erythroid-progenitor cell number increased in the spleen of Pk-1slc/Pk-1slc mice to a level approximately 66 times higher than that in normal CBA mice, suggesting that compensatory extramedullary erythropoiesis in the spleen of the mutant mice, but not in the human variant, might account for the observed difference in the phenotype.

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Primary structure of murine red blood cell-type pyruvate kinase (PK) and molecular characterization of PK deficiency identified in the CBA strain

Blood ◽

10.1182/blood.v86.8.3205.bloodjournal8683205 ◽

1995 ◽

Vol 86 (8) ◽

pp. 3205-3210 ◽

Cited By ~ 1

Author(s):

H Kanno ◽

M Morimoto ◽

H Fujii ◽

T Tsujimura ◽

H Asai ◽

...

Keyword(s):

Amino Acid ◽

Blood Cell ◽

Missense Mutation ◽

Pyruvate Kinase ◽

Red Blood Cell ◽

Cdna Sequence ◽

Amino Acid Change ◽

Mutant Mice ◽

Cell Type ◽

Blood Cell Type

To clarify the molecular abnormality of pyruvate kinase (PK) deficiency identified in the mutant mice of CBA-Pk-1slc/Pk-1slc, we cloned murine red blood cell-type PK (R-PK) cDNA of those animals. The cDNA sequence spans 1827 bp, including an open reading frame that can encode 574 amino acids. Homology in the coding sequences between murine and human R-PK was 86.1% at nucleotide and 91.5% at amino acid levels. A homozygous missense mutation at nucleotide 1013 GGT-->GAT was identified in the cDNA sequence of the mutant, causing a single amino acid substitution at no. 338Gly-->Asp of the murine R-PK. Six amino acid residues, 335Val-336Ala-337Arg-338Gly-339Asp-340L eu, were encoded in exon 8 of both human and rat L (liver-type)/R-PK genes and were evolutionarily conserved in PK from bacteria through humans. 337Arg was reported to be important for substrate binding, suggesting that the amino acid change would impair substrate affinity of the PK subunit. A homozygous missense mutation at the catalytic domain has been identified in a human PK variant, PK Hong Kong (941ATT-->ACT, 314 Ile-- >Thr). Although both 1013A and 941C gave rise to an amino acid change adjacent to the active site and may interfere with substrate binding to the subunit, the degree of anemia was much more severe in the human case. The erythroid-progenitor cell number increased in the spleen of Pk-1slc/Pk-1slc mice to a level approximately 66 times higher than that in normal CBA mice, suggesting that compensatory extramedullary erythropoiesis in the spleen of the mutant mice, but not in the human variant, might account for the observed difference in the phenotype.

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The role of policy in red blood cell storage and transfusion in children

Pediatric Research ◽

10.1038/pr.2017.213 ◽

2017 ◽

Vol 82 (6) ◽

pp. 894-896

Author(s):

Jean L Raphael ◽

Keyword(s):

Blood Cell ◽

Red Blood Cell ◽

Cell Storage

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Recent insights into nitrite signaling processes in blood

Biological Chemistry ◽

10.1515/hsz-2016-0263 ◽

2017 ◽

Vol 398 (3) ◽

pp. 319-329 ◽

Cited By ~ 9

Author(s):

Christine C. Helms ◽

Xiaohua Liu ◽

Daniel B. Kim-Shapiro

Keyword(s):

Nitric Oxide ◽

Human Physiology ◽

Blood Cell ◽

Red Blood Cell ◽

Nitrite Reduction ◽

No Production ◽

The Past ◽

Acidic Conditions ◽

Hypoxic Vasodilation

Abstract Nitrite was once thought to be inert in human physiology. However, research over the past few decades has established a link between nitrite and the production of nitric oxide (NO) that is potentiated under hypoxic and acidic conditions. Under this new role nitrite acts as a storage pool for bioavailable NO. The NO so produced is likely to play important roles in decreasing platelet activation, contributing to hypoxic vasodilation and minimizing blood-cell adhesion to endothelial cells. Researchers have proposed multiple mechanisms for nitrite reduction in the blood. However, NO production in blood must somehow overcome rapid scavenging by hemoglobin in order to be effective. Here we review the role of red blood cell hemoglobin in the reduction of nitrite and present recent research into mechanisms that may allow nitric oxide and other reactive nitrogen signaling species to escape the red blood cell.

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A Comparison of CO2 Excretion IA Spontaneously Ventilating Blood Perfused Trout Preparation and Salineperfused Gill Preparations: Contribution of the Branchial Epithelium and Red Blood Cell

Journal of Experimental Biology ◽

10.1242/jeb.101.1.47 ◽

1982 ◽

Vol 101 (1) ◽

pp. 47-60 ◽

Cited By ~ 1

Author(s):

STEVE F. PERRY ◽

PETER S. DAVIE ◽

DAVID J. RANDALL

Keyword(s):

Blood Cell ◽

Red Blood Cell ◽

Coho Salmon ◽

Disulfonic Acid ◽

Gill Epithelium ◽

Rate Limiting Step ◽

Branchial Epithelium ◽

Epithelium Cells ◽

Co2 Excretion

A spontaneously ventilating blood-perfused trout preparation and saline perfused gill preparations were utilized to investigate the role of the erythrocyte and branchial epithelium in CO2 excretion and acid-base regulation. CO, excretion (MCOCO2) in blood-perfused preparations was positively correlated with haematocrit (Hct), and was abolished completely during plasma-perfusion. Elevating HCO3- concentration of input blood from 10 to 25 mM significantly increased MCOCO2. fourfold in blood-perfused preparations as a result of increased entry of HCO into the red blood cell and not into the gill epithelium. Increased HCO3- concentration was without effect in totally saline-perfused coho salmon (Onchorynchus kisutch). The addition of 4-acetamido-4′-wo-thiocyanatostilbene-2, 2 disulfonic acid (SITS; 10−4 M) to input blood significantly reduced MCO, and oxygen uptake (Mg,OO2) in blood-perfused fish due to inhibition of erythrocytic HCO3-exchange. Unlike blood-perfused preparations, no saline-perfused preparation (isolated holobranchs or totally perfused rainbow trout or coho salmon) displayed measureable CO, excretion at physiological Pco and pH. Increased input PCOt in both blood-perfused and saline-perfused preparations significantly increased MCOt due to enhanced branchial diffusion of molecular CO2. It is concluded that the entry of HCO3- into the erythrocyte is the rate-limiting step in CO, excretion and that movement of HCO3- from plasma to gill epithelium cells in no way contributes to overall CO3 elimination. Note: Department of Physiology and Anatomy, Massey University Palmerston North, New Zealand. Pacific Gamefish Foundation, P.O. Box 25115, Honolulu, Hawaii, U.S.A. 96825

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