Deoxygenation Affects Composition of Membrane-Bound Proteins in Human Erythrocytes.
OBJECTIVE
ATP release from erythrocyte plays a key role in hypoxia-induced elevation of blood flow in systematic circulation. We have previously shown that hemolysis contributes to erythrocyte ATP release triggered by several stimuli, including hypoxia, but the molecular mechanisms of hypoxia-increased membrane fragility remain unknown.


METHODS
In this study, we compared the action of hypoxia on hemolysis, ATP release and the composition of membrane-bound proteins in human erythrocytes.


RESULTS
Twenty minutes incubation of human erythrocytes in the oxygen-free environment increased the content of extracellular hemoglobin by ∼1.5 fold. Paired measurements of hemoglobin and ATP content in the same samples, showed a positive correlation between hemolysis and ATP release. Comparative analysis of SDS-PAGE electrophoresis of erythrocyte ghosts obtained under control and deoxygenated conditions revealed a ∼2-fold elevation of the content of membrane-bound protein with Mr of ∼60 kDa.


CONCLUSIONS
Deoxygenation of human erythrocytes affects composition of membrane-bound proteins. Additional experiments should be performed to identify the molecular origin of 60 kDa protein and its role in the attenuation of erythrocyte integrity and ATP release in hypoxic conditions.
Faculty of Biology, M.V. Lomonosov Moscow State University Moscow, Russia.
Oksana G
OG
Luneva
Svetlana V
SV
Sidorenko
Olga O
OO
Ponomarchuk
Artem M
AM
Tverskoy
Aleksander A
AA
Cherkashin
Oleg V
OV
Rodnenkov
Natalia V
NV
Alekseeva
Leonid I
LI
Deev
Georgy V
GV
Maksimov
Ryszard
R
Grygorczyk
Sergei N
SN
Orlov
D000255:Adenosine Triphosphate / Q000378:metabolism; D000328:Adult; D015687:Cell Hypoxia; D004591:Electrophoresis, Polyacrylamide Gel; D004910:Erythrocyte Membrane / Q000378:metabolism; D004912:Erythrocytes / Q000378:metabolism*; D005260:Female; D006454:Hemoglobins / Q000378:metabolism*; D006461:Hemolysis; D006801:Humans; D016014:Linear Models; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism*; D013997:Time Factors; D055815:Young Adult
D006454:Hemoglobins; D008565:Membrane Proteins; D000255:Adenosine Triphosphate; D010100:Oxygen