scholarly journals The response of red cell hexose monophosphate shunt after sulfhydryl inhibition

Blood ◽  
1975 ◽  
Vol 45 (1) ◽  
pp. 49-54 ◽  
Author(s):  
AL Jr Sagone ◽  
SP Balcerzak ◽  
EN Metz
Keyword(s):  
Carbon Monoxide ◽  
Ionization Chamber ◽  
Human Erythrocytes ◽  
Red Cells ◽  
Red Cell ◽  
Hexose Monophosphate ◽  
Peroxide Formation ◽  
Hexose Monophosphate Shunt ◽  
Vibrating Reed ◽  
Stimulation Of

Abstract In this investigation, we studied the importance of cellular glutathione (GSH) in the hexose monophosphate shunt (HMPS) activity of unstimulated human erythrocytes and the mechanism by which pyruvate stimulates the HMPS. The rate of HMPS activity was measured by the production of radioactive CO2 from 14C-1-glucose or 14C-1-ribose using a vibrating reed electrometer and ionization chamber. HMPS activity was not significantly impaired by N-ethylmaleimide (NEM) in concentrations which bound all red cell GSH. Red cells incubated under carbon monoxide (CO), an experimental condition which eliminates peroxide production, still had HMPS activity which was 44% of the value under air. Pyruvate stimulation of the HMPS was unaffected by doses of NEM which bound all cellular GSH or by incubation under CO. These data indicated that pyruvate stimulation of the HMPS occurs by pathways which do not involve peroxide formation, GSH, or oxygen. This study indicates that sulfhydrylblockade of GSH does not necessarily inhibit HMPS activity and that HMPS activity in red cells may respond to reactions not linked directly to glutathione reduction.

scholarly journals The response of red cell hexose monophosphate shunt after sulfhydryl inhibition

Blood ◽  
1975 ◽  
Vol 45 (1) ◽  
pp. 49-54
Author(s):  
AL Jr Sagone ◽  
SP Balcerzak ◽  
EN Metz
Keyword(s):  
Carbon Monoxide ◽  
Ionization Chamber ◽  
Human Erythrocytes ◽  
Red Cells ◽  
Red Cell ◽  
Hexose Monophosphate ◽  
Peroxide Formation ◽  
Hexose Monophosphate Shunt ◽  
Vibrating Reed ◽  
Stimulation Of

In this investigation, we studied the importance of cellular glutathione (GSH) in the hexose monophosphate shunt (HMPS) activity of unstimulated human erythrocytes and the mechanism by which pyruvate stimulates the HMPS. The rate of HMPS activity was measured by the production of radioactive CO2 from 14C-1-glucose or 14C-1-ribose using a vibrating reed electrometer and ionization chamber. HMPS activity was not significantly impaired by N-ethylmaleimide (NEM) in concentrations which bound all red cell GSH. Red cells incubated under carbon monoxide (CO), an experimental condition which eliminates peroxide production, still had HMPS activity which was 44% of the value under air. Pyruvate stimulation of the HMPS was unaffected by doses of NEM which bound all cellular GSH or by incubation under CO. These data indicated that pyruvate stimulation of the HMPS occurs by pathways which do not involve peroxide formation, GSH, or oxygen. This study indicates that sulfhydrylblockade of GSH does not necessarily inhibit HMPS activity and that HMPS activity in red cells may respond to reactions not linked directly to glutathione reduction.

scholarly journals Red cell diphosphoglycerate mutase. Immunochemical studies in vertebrate red cells, including a human variant lacking 2,3-DPG

Blood ◽  
1978 ◽  
Vol 52 (5) ◽  
pp. 953-958 ◽  
Author(s):  
LL Peterson
Keyword(s):  
Enzyme Activity ◽  
Genetic Variant ◽  
Neonatal Period ◽  
Human Erythrocytes ◽  
Red Cells ◽  
The Other ◽  
Radial Immunodiffusion ◽  
Red Cell ◽  
Human Adult ◽  
2,3 Dpg

Abstract Diphosphoglycerate mutase (DPGM) was purified to homogeneity from human erythrocytes. The enzyme and Freund adjuvant were injected into chickens and yielded a monospecific precipitating antibody. Radial immunodiffusion with this antibody was used to measure the amount of DPGM in hemolysates from human adult and cord red cells. Dog, rabbit, rat, chicken, and goat red cells all had DPGM during the neonatal period, but goat adult red cells had no detectable enzyme. Single bands with no spurs were present on Ouchterlony plates in which human hemolysate was placed adjacent to hemolysates from the other species tested. The amount of human red cell DPGM did not differ between young and old cells separated by centrifugation. Red cells from a patient with a DPGM genetic variant who had erythrocytosis and no detectable enzyme activity contained a reduced amount of DPGM as determined by radial immunodiffusion. The abnormal DPGM differed from normal by immunoelectrophoresis and in stability as measured by the amount of crossreacting material in young versus old erythrocytes.

scholarly journals Red cell diphosphoglycerate mutase. Immunochemical studies in vertebrate red cells, including a human variant lacking 2,3-DPG

Blood ◽  
1978 ◽  
Vol 52 (5) ◽  
pp. 953-958
Author(s):  
LL Peterson
Keyword(s):  
Enzyme Activity ◽  
Genetic Variant ◽  
Neonatal Period ◽  
Human Erythrocytes ◽  
Red Cells ◽  
The Other ◽  
Radial Immunodiffusion ◽  
Red Cell ◽  
Human Adult ◽  
2,3 Dpg

Diphosphoglycerate mutase (DPGM) was purified to homogeneity from human erythrocytes. The enzyme and Freund adjuvant were injected into chickens and yielded a monospecific precipitating antibody. Radial immunodiffusion with this antibody was used to measure the amount of DPGM in hemolysates from human adult and cord red cells. Dog, rabbit, rat, chicken, and goat red cells all had DPGM during the neonatal period, but goat adult red cells had no detectable enzyme. Single bands with no spurs were present on Ouchterlony plates in which human hemolysate was placed adjacent to hemolysates from the other species tested. The amount of human red cell DPGM did not differ between young and old cells separated by centrifugation. Red cells from a patient with a DPGM genetic variant who had erythrocytosis and no detectable enzyme activity contained a reduced amount of DPGM as determined by radial immunodiffusion. The abnormal DPGM differed from normal by immunoelectrophoresis and in stability as measured by the amount of crossreacting material in young versus old erythrocytes.

THE EFFECTS OF CERTAIN DRUGS ON THE HEXOSE MONOPHOSPHATE SHUNT OF HUMAN RED CELLS

1971 ◽  
Vol 179 (1 Drug Metaboli) ◽  
pp. 625-635 ◽  
Author(s):  
Selman I. Welt ◽  
Elizabeth H. Jackson ◽  
Henry N. Kirkman ◽  
John C. Parker
Keyword(s):  
Red Cells ◽  
Hexose Monophosphate ◽  
Hexose Monophosphate Shunt ◽  
Human Red Cells

scholarly journals Lipid peroxidation and haemoglobin degradation in red blood cells exposed to t-butyl hydroperoxide. Effects of the hexose monophosphate shunt as mediated by glutathione and ascorbate

1982 ◽  
Vol 204 (2) ◽  
pp. 405-415 ◽  
Author(s):  
R J Trotta ◽  
S G Sullivan ◽  
A Stern
Keyword(s):  
Lipid Peroxidation ◽  
Blood Cells ◽  
Synergistic Effects ◽  
Red Cells ◽  
Hexose Monophosphate ◽  
Butyl Hydroperoxide ◽  
Hexose Monophosphate Shunt ◽  
Low Concentrations ◽  
Exact Position ◽  
High Concentrations

Lipid peroxidation and haemoglobin degradation were the two extremes of a spectrum of oxidative damage in red cells exposed to t-butyl hydroperoxide. The exact position in this spectrum depended on the availability of glucose and the ligand state of haemoglobin. In red cells containing oxy- or carbonmono-oxy-haemoglobin, hexose monophosphate-shunt activity was mainly responsible for metabolism of t-butyl hydroperoxide; haem groups were the main scavengers in red cells containing methaemoglobin. Glutathione, via glutathione peroxidase, accounted for nearly all of the hydroperoxide metabolizing activity of the hexose monophosphate shunt. Glucose protection against lipid peroxidation was almost entirely mediated by glutathione, whereas glucose protection of haemoglobin was only partly mediated by glutathione. Physiological concentrations of intracellular or extracellular ascorbate had no effect on consumption of t-butyl hydroperoxide or oxidation of haemoglobin. Ascorbate was mainly involved in scavenging chain-propagating species involved in lipid peroxidation. The protective effect of intracellular ascorbate against lipid peroxidation was about 100% glucose-dependent and about 50% glutathione-dependent. Extracellular ascorbate functioned largely without a requirement for glucose metabolism, although some synergistic effects between extracellular ascorbate and glutathione were observed. Lipid peroxidation was not dependent on the rate or completion of t-butyl hydroperoxide consumption but rather on the route of consumption. Lipid peroxidation appears to depend on the balance between the presence of initiators of lipid peroxidation (oxyhaemoglobin and low concentrations of methaemoglobin) and terminators of lipid peroxidation (glutathione, ascorbate, high concentrations of methaemoglobin).

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