Control of glycolysis in human erythrocytes by inorganic phosphate and sulfate

Sc, Rizzo; Eckel, RE

doi:10.1152/ajplegacy.1966.211.2.429

Cited by 34 publications

(14 citation statements)

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“…The concentration of plasma Pi has been reported to influence the metabolism of red cells in vivo and in vitro (8, 12-14, 16, 17, 19, 23). An increase in the Pi concentration of the medium in vitro is associated with an increased glycolytic rate and an accumulation of triose phosphates and fructose diphosphate (total triose phosphate), 2,3-DPG, and ATP (12,14,(17)(18)(19). These changes are dependent on the pH of the medium (14) and are greatest at pH 8.0, where the glycolytic rate is almost maximal.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Red Cell Metabolic Alterations in Postnatal Life in Term Infants: Possible Control Mechanisms

Travis

Kumar

Delivoria‐Papadopoulos

1981

Pediatr Res

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SummaryRed cell glycolytic intermediates and enzymes in term infants in the first year of life were correlated with the fetal hemoglobin concentration (%F), intra-and extracellular venous pH, plasma inorganic phosphorus (Pi) and pyruvate kinase (PK) activity.. .changes in the non-age-dependent enzymes phosphoglycerate kinase. enolase. and phosphofructokinase correlated most significantly with the postnatalhecline in %F ( P c 0.001), not the age of the red cell population, as reflected in PK activity. The agedependent enzymes, hexokinase and glucosedphosphate deh$drogenase, however, correlated well with PK activity ( P C 0.001). The concentration of glucosedphosphate did not correlate significantly with the postnatal decline in %F ( P > 0.05) or PK ( P > 0.10), but correlated significantly with the plasma Pi concentration (P < 0.001). "Total triose phosphate" and 2,3diphosphogIyceratedid not correlate with Pi.It appears from these studies that an extracellular factor, Pi, alters the pattern of glycolytic intermediates in term infants and that the postnatal changes in phosphoglycerate kinase, enolase, and phosphofructokinase are unique to the "fetal" red cell and reflect passage from fetal to "adult" erythropoiesis. SpeculationIt is proposed that the rise in the glucosedphosphate concentration in red cells from term infants previously reported is secondary to a combination of stimulation of hexokinase activity by plasma inorganic phosphorus and a relative block in glycolysis at the phosphofructokinase (PFK) step secondary to both decreased enzyme activity and decreased activation of PFK by plasma inorganic phosphorus. It is speculated from these studies that the relative block in glycolysis at the PFK step previously described in term infants is probably greater at the in vivo level than that Analysis of red cell glywlytic intermediates (21). however, revealed that the wncentration of glucose-6-phosphate (G-6-P) continued to increase from day I to wk 3 to 4 despite PFK activity that remained essentially unchanged (22). This pattern of glycolytic intermediates was suggestive of a block in glywlysis at the PFK step that was modulated by factors other than enzyme activity alone.It has been well established that changes in the extracellular concentration of inorganic phosphorus (Pi) can profoundly affect the metabolism of the human red cell (8, 12-14, 16, 17, 19, 23). 13,16,23) and hyperphosphatemia (12,(14)(15)(16)(17)19) have been correlated with changes in the glycolytic rate and the pattern of red cell glycolytic intermediates and adenosine triphosphate (ATP) both in vitro and in vivo. The pattern of these changes in the intermediates is dependent on the pH of the medium (14). Because hyperphosphatemia is common in the newborn period (1,3,4,7,24) and acidosis has been reported, it would appear that both the plasma Pi wncentration and intracellular pH may modify the metabolism and, hence, the pattern of glywlytic intermediates in neonatal red cells.Thus, red cell intracellular and extracellular pH and the plasma Pi...

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Section: Discussionmentioning

confidence: 99%

“…13,16,23) and hyperphosphatemia (12,(14)(15)(16)(17)19) have been correlated with changes in the glycolytic rate and the pattern of red cell glycolytic intermediates and adenosine triphosphate (ATP) both in vitro and in vivo. The pattern of these changes in the intermediates is dependent on the pH of the medium (14).…”

Section: Speculationmentioning

confidence: 99%

Red Cell Metabolic Alterations in Postnatal Life in Term Infants: Possible Control Mechanisms

Travis

Kumar

Delivoria‐Papadopoulos

1981

Pediatr Res

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“…The reaction catalysed by hexokinase is one of the rate-limiting steps in glucose metabolism, and the control is exerted through activation (Pi) or inhibition (glucose-6-phosphate) of the reaction (Rose & O'Connell, 1964). The glucose consumption of fresh cells is raised by Pi as is the consumption of nucleosides (Chapman, Hennessey, Waltersdorph, Huennekens & Gabrio, 1962;Tsuboi & Fukunaga, 1965; Minakami, Kakinuma & Yoshikawa, 1964;Rizzo & Eckel, 1966). Intracellular Pi acts by relieving the inhibition of the hexokinase reaction by glucose-6-phosphate (Rose, Warms & O'Connell, 1964), and also causes a fall in the concentration of glucose-6-phosphate (Rizzo & Eckel, 1966).…”

Section: Metabolism Of Nucleosides and Glucosementioning

confidence: 99%

“…The glucose consumption of fresh cells is raised by Pi as is the consumption of nucleosides (Chapman, Hennessey, Waltersdorph, Huennekens & Gabrio, 1962;Tsuboi & Fukunaga, 1965; Minakami, Kakinuma & Yoshikawa, 1964;Rizzo & Eckel, 1966). Intracellular Pi acts by relieving the inhibition of the hexokinase reaction by glucose-6-phosphate (Rose, Warms & O'Connell, 1964), and also causes a fall in the concentration of glucose-6-phosphate (Rizzo & Eckel, 1966). The present results show that glucose metabolism is also stimulated by raising the ATP content of the cells in agreement with Bishop (1964) and Tsuboi et al (1966).…”

Section: Metabolism Of Nucleosides and Glucosementioning

confidence: 99%

Potassium transport and nucleoside metabolism in human red cells

Whittam¹,

Wiley²

1967

The Journal of Physiology

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SUMMARY1. A study has been made of active cation transport in relation to the metabolism of nucleosides and deoxynucleosides in human red blood cells.2. Lactate production from inosine depended on the cellular inorganic phosphate available for phosphorolysis and was raised to some 4 times the normal rate from glucose. Inosine inhibited glucose metabolism according to the amount of glucose-6-phosphate produced. Guanosine behaved similarly, but glucose-6-phosphate was not formed from adenosine, deoxyinosine and deoxyguanosine.3. Glucose metabolism was related to the ATP content of the cells, which was raised by incubation with adenosine, or with inosine plus adenine.4. Adenosine and deoxyadenosine raised the potassium influx above the values found with inosine and deoxyinosine under conditions when the lactate production was constant. Active potassium influx was correlated with the ATP concentration in the cells, but independent of the lactate produ ction when the latter was raised above normal.

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“…It occurred to us that this difference might be due to an activating effect of the sulfate ions similar to that of phosphate ions. A stimulating effect of sulfate ions on the phosphofructokinase had been suggested earlier on the basis of an increase of glycolysis of erythrocytes after addition of sodium sulfate [4,5]. Some measurements of the phosphofructokinase activity in hemolysates support the assumption of a sulfate activation of the enzyme.…”

Section: Introductionmentioning

confidence: 70%