General Physiology and Biophysics Vol.34, No.3, p.311–321, 2015
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Title: The action of stress hormones on the structure and function of erythrocyte membrane |
Author: Pavel V. Mokrushnikov, Lev E. Panin, Boris N. Zaitsev |
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Abstract: The action of a mixture of hormones (cortisol and adrenaline) on erythrocyte membrane during their binding was investigated. Changes in the membrane structure were elucidated by atomic force microscopy; microviscosity of the lipid bilayer and changes in the activity of Na+,K+-ATPase at different concentrations of the hormones in erythrocyte suspension were estimated by the fluorescence method. Cortisol and adrenaline were shown to compete for the binding sites. A hormone that managed to bind nonspecifically to the membrane hindered the binding of another hormone. In a mixture of these hormones, cortisol won a competition for the binding sites; therewith, microviscosity of the membranes increased by 25%, which corresponds to a change in microviscosity produced by the action of cortisol alone. The competitive relationships affected also the Na+,K+-ATPase activity, which was indicated by appearance of the second maximum of enzyme activity. It is assumed that an increase in microviscosity of erythrocyte membrane first raises the Na+,K+-ATPase activity due to a growth of the maximum energy of membrane phonons, and then decreases the activity due to hindering of conformational transitions in the enzyme molecule.
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Keywords: Erythrocyte membranes — Stress hormones — Atomic force microscopy — Structural transitions — Na+,K+-ATPase activity — Membrane phonons |
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Published online: 23-Jun-2015
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Year: 2015, Volume: 34, Issue: |
Page From: 311, Page To: 321 |
doi:10.4149/gpb_2014041
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