Year-end Sale % OFF 
Abstract
The effect of hydrostatic pressure at levels applied in diving or hyperbaric treatment (thus considered "physiological") on the order of lipid domains in human red blood cell (RBC) membrane was studied. Membrane order was determined by measuring 1) the fluorescence anisotropy (FAn) of lipid probes, 2) the resonance energy transfer from tryptophan to lipid probes, and 3) spectral shifts in Laurdan fluorescence emission. It was found that the application of mild pressure (< 15 atm) 1) increased, selectively, the FAn of lipid probes that monitor the membrane lipid core, 2) increased the tryptophan FAn, 3) increased the resonance energy transfer from tryptophan to lipid probes residing in the lipid core, and 4) induced changes in the Laurdan fluorescence spectrum, which corresponded to reduced membrane hydration. It is proposed that the application of pressure of several atmospheres increases the phase order of membrane lipid domains, particularly in the proximity of proteins. Because the membrane lipid order ("fluidity") of RBCs plays an important role in their cellular and rheological functions, the pressure-induced alterations of the RBC membrane might be pertinent to microcirculatory disorders observed in humans subjected to elevated pressure.
Highlights
Title Membrane lipid order of human red blood cells is altered by physiological levels of hydrostatic pressure
It was found that the application of mild pressure (~15 atm) 1) increased, selectively, the fluorescence anisotropy (FAn) of lipid probes that monitor the membrane lipid core, 2) increased the tryptophan FAn, 3) increased the resonance energy transfer from tryptophan to lipid probes residing in the lipid core, and 4) induced changes in the Laurdan fluorescence spectrum, which corresponded to reduced membrane hydration
To learn about a possible differential pressure effect on the order of different lipid domains in the RBC membranes, we measured the FAn of the lipid probes listed in METHODS, which reside in different lipid regions of the RBC membrane, as well as the energy transfer from tryptophan to these probes
Summary
Title Membrane lipid order of human red blood cells is altered by physiological levels of hydrostatic pressure. Membrane lipid order of human red blood cells is altered by physiological levels of hydrostatic pressure. 41): H538-H543, 1997.-The effect of hydrostatic pressure at levels applied in diving or hyperbaric treatment ( considered “physiological”) on the order of lipid domains in human red blood cell (RBC) membrane was studied. It was observed that the application of hydrostatic pressure in the range of several atmospheres to RBCs induces changes in the membrane composition, leading to resistance of the cells to hemolysis by phospholipase AZ [11] and to enhancement of their aggregability [6]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: American Journal of Physiology-Heart and Circulatory Physiology
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
