Kinetic Characteristics of Ca2+-ATPase of Erythrocytes in PEO-1500 Presence

Authors

  • N. G. Zemlyanskikh
  • L. A. Babijchuk
  • A. Yu. Nikolchenko
  • V. P. Tyagileva

Keywords:

erythrocytes, Ca2 -ATPase, cryoprotectants, polyethylene oxide

Abstract

In the work it has been established, that the exocellular cryoprotectant PEO-1500 inhibits the activity of Ca2+-ATPase of erythrocytes. Kinetic analysis showed that the inhibition of enzyme activity was related to the Vmax alteration, but not to Km for catalytic center with a low affinity of Ca2+-ATPase. The highly affinic center of Ca2+-ATPase was not modified under PEO-1500 effect. The presence of cryoprotectant in the medium reduces the sensitivity of enzyme response of ATP hydrolysis to Ca2+ ions, as the result the erythrocyte Ca2+-ATPase functioning is activated in a lesser extent within the range of Ca2+ low concentrations and is inhibited in a greater extent for a high concentration range of this ion in comparison with the native erythrocytes. These data allow to suggest, that under PEO-1500 effect the Ca2+-ATPase ion-transporting function can be suppressed, and the efficiency of Ca-pump activity will decrease. The inhibition of Ca2+-ATPase activity is evidently caused by modifying the physical and chemical characteristics of plasma membrane under PEO-1500 effect.

Author Biographies

N. G. Zemlyanskikh

Institute for Problems of Cryobiology and Cryomedicine of the National Academy of Sciences of Ukraine, Kharkiv

L. A. Babijchuk

Institute for Problems of Cryobiology and Cryomedicine of the National Academy of Sciences of Ukraine, Kharkiv

A. Yu. Nikolchenko

Institute for Problems of Cryobiology and Cryomedicine of the National Academy of Sciences of Ukraine, Kharkiv

V. P. Tyagileva

Institute for Problems of Cryobiology and Cryomedicine of the National Academy of Sciences of Ukraine, Kharkiv

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Published

2003-12-25

How to Cite

Zemlyanskikh, N. G., Babijchuk, L. A., Nikolchenko, A. Y., & Tyagileva, V. P. (2003). Kinetic Characteristics of Ca2+-ATPase of Erythrocytes in PEO-1500 Presence. Problems of Cryobiology and Cryomedicine, (4), 28–34. Retrieved from http://cryo.org.ua/journal/index.php/probl-cryobiol-cryomed/article/view/1075

Issue

Section

Theoretical and Experimental Cryobiology