Vesiculation Induced by Hydrostatic Pressure in Human Erythrocytes

Abstract

When human erythrocytes were subjected to hydrostatic pressure (1.1-2.0 kbar), it was found that membrane vesicles were released from the red cells above 1.4 kbar. As with hemolysis under high pressure, the amount of released vesicles was increased with increasing pressure but decreased by the cross-linking of membrane proteins with diamide. Vesicles obtained at 2.0 kbar were heterogeneous in size but similar to intact erythrocytes in phospholipid composition. Although it has been reported that spectrin-free vesicles are released by echinocytogenic agents, pressure-induced vesicles did contain considerable and similar amounts of spectrin irrespective of the difference in size. These results suggest that vesiculation by high pressure is associated with the disruption of the membrane skeleton, as previously seen in pressure-induced hemolysis [Yamaguchi et al. (1989) J. Biochem. 106, 1080-1085].

Effects of Cholesterol on Membrane Stability of Human Erythrocytes

“…25 °C), and the absorbance of hemoglobin in the supernatant was measured at 542 nm. 4) Moreover, the properties of particles produced from the erythrocytes by pressure were measured using an EPICS XL-MCL flow cytometer (Coulter, U.S.A.). 7) The morphology of pressuretreated erythrocytes was examined using a scanning electron microscope (SEM).…”

“…When the erythrocytes suspended in isotonic buffer are exposed to a high hydrostatic pressure (simply, called pressure), the cells are compressed so that the vesiculation, fragmentation, and hemolysis occur. [4][5][6][7] The proportion of vesicles, fragmented particles, and open ghosts is modulated by the properties of the erythrocyte membrane. 6,7) The pressure-induced hemolysis is dependent on the size of vesicles released from the membrane surface.…”

ATP effects on response of human erythrocyte membrane to high pressure

“…Rheological study of erythrocytes has been performed using various methods such as ektacytometer [11], pipette aspiration technique [16], high pressure [17,18], etc. Force applied to erythrocytes in the ektacytometer and pipette aspiration technique is anisotropic, whereas isotropic force is applied to them in the case of high pressure.…”

“…The pipette aspiration technique is suitable to detect the integral proteins that are not linked to cytoskeletal proteins [16]. On the other hand, we have been demonstrating that the response of the erythrocyte membrane to high pressure reflects the bilayer-cytoskeleton interaction [18,20]. When human erythrocytes are exposed to high pressures for 30 min at 37°C, the hemolysis, vesiculation, and fragmentation begin to occur at 140 MPa and the value of hemolysis at 200 MPa is about 50% [18,21,22].…”

“…On the other hand, we have been demonstrating that the response of the erythrocyte membrane to high pressure reflects the bilayer-cytoskeleton interaction [18,20]. When human erythrocytes are exposed to high pressures for 30 min at 37°C, the hemolysis, vesiculation, and fragmentation begin to occur at 140 MPa and the value of hemolysis at 200 MPa is about 50% [18,21,22]. This value of hemolysis at 200 MPa changes sensitively upon membrane perturbation [20,22,23].…”